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Bring SQL ref pages to consistent format, part 1.

This commit is contained in:
Peter Eisentraut 2003-04-15 13:25:08 +00:00
parent 72aa9488d3
commit 7c084d148f
14 changed files with 1261 additions and 1797 deletions
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160
doc/src/sgml/ref/abort.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/abort.sgml,v 1.11 2002/04/21 19:02:39 thomas Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/abort.sgml,v 1.12 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,130 +8,82 @@ PostgreSQL documentation
<refentrytitle id="sql-abort-title">ABORT</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
ABORT
</refname>
<refpurpose>
abort the current transaction
</refpurpose>
<refname>ABORT</refname>
<refpurpose>abort the current transaction</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
ABORT [ WORK | TRANSACTION ]
</synopsis>
<refsect2 id="R2-SQL-ABORT-1">
<refsect2info>
<date>1998-09-27</date>
</refsect2info>
<title>
Inputs
</title>
<para>
None.
</para>
</refsect2>
<refsect2 id="R2-SQL-ABORT-2">
<refsect2info>
<date>1998-09-27</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
ROLLBACK
</computeroutput></term>
<listitem>
<para>
Message returned if successful.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>
WARNING: ROLLBACK: no transaction in progress
</computeroutput></term>
<listitem>
<para>
If there is not any transaction currently in progress.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-ABORT-1">
<refsect1info>
<date>1998-09-27</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>ABORT</command> rolls back the current transaction and causes
all the updates made by the transaction to be discarded.
This command is identical
in behavior to the <acronym>SQL92</acronym> command <command>ROLLBACK</command>,
in behavior to the standard <acronym>SQL</acronym> command <command>ROLLBACK</command>,
and is present only for historical reasons.
</para>
<refsect2 id="R2-SQL-ABORT-3">
<refsect2info>
<date>1998-09-27</date>
</refsect2info>
<title>
Notes
</title>
<para>
Use <command>COMMIT</command> to successfully
terminate a transaction.
</para>
</refsect2>
</refsect1>
<refsect1 id="R1-SQL-ABORT-2">
<title>
Usage
</title>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>ROLLBACK</computeroutput></term>
<listitem>
<para>
Message returned if successful.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>WARNING: ROLLBACK: no transaction in progress</computeroutput></term>
<listitem>
<para>
If there is not any transaction currently in progress.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
Use <command>COMMIT</command> to successfully
terminate a transaction.
</para>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
To abort all changes:
<programlisting>
<programlisting>
ABORT WORK;
</programlisting>
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-ABORT-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-ABORT-4">
<refsect2info>
<date>1998-09-27</date>
</refsect2info>
<title>
SQL92
</title>
<para>
This command is a <productname>PostgreSQL</productname> extension present
for historical reasons. <command>ROLLBACK</command> is the <acronym>SQL92</acronym>
equivalent command.
</para>
</refsect2>
<para>
This command is a <productname>PostgreSQL</productname> extension
present for historical reasons. <command>ROLLBACK</command> is the
equivalent standard SQL command.
</para>
</refsect1>
</refentry>

16
doc/src/sgml/ref/alter_database.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_database.sgml,v 1.5 2003/03/25 16:15:38 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_database.sgml,v 1.6 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -32,18 +32,18 @@ ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> RESET <replacea
value becomes the session default value.
The database-specific default
overrides whatever setting is present in <filename>postgresql.conf</>
or has been received from the postmaster.
or has been received from the <command>postmaster</command> command line.
</para>
<para>
Only a superuser or the database owner can change the session defaults for a
Only the database owner or a superuser can change the session defaults for a
database.
</para>
</refsect1>
<refsect2>
<title>Parameters</title>
<refsect1>
<title>Parameters</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">name</replaceable></term>
@ -77,14 +77,11 @@ ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> RESET <replacea
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER DATABASE</computeroutput></term>
@ -105,7 +102,6 @@ ALTER DATABASE <replaceable class="PARAMETER">name</replaceable> RESET <replacea
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1>

158
doc/src/sgml/ref/alter_group.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_group.sgml,v 1.8 2002/04/21 19:02:39 thomas Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_group.sgml,v 1.9 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,92 +8,29 @@ PostgreSQL documentation
<refentrytitle id="SQL-ALTERGROUP-title">ALTER GROUP</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
ALTER GROUP
</refname>
<refpurpose>
add users to a group or remove users from a group
</refpurpose>
<refname>ALTER GROUP</refname>
<refpurpose>add users to a group or remove users from a group</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>2000-01-14</date>
</refsynopsisdivinfo>
<synopsis>
ALTER GROUP <replaceable class="PARAMETER">name</replaceable> ADD USER <replaceable class="PARAMETER">username</replaceable> [, ... ]
ALTER GROUP <replaceable class="PARAMETER">name</replaceable> DROP USER <replaceable class="PARAMETER">username</replaceable> [, ... ]
</synopsis>
<refsect2 id="R2-SQL-ALTERGROUP-1">
<refsect2info>
<date>2000-01-14</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">name</replaceable></term>
<listitem>
<para>
The name of the group to modify.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">username</replaceable></term>
<listitem>
<para>
Users which are to be added or removed from the group. The user
names must exist.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-ALTERGROUP-2">
<refsect2info>
<date>2000-01-14</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER GROUP</computeroutput></term>
<listitem>
<para>
Message returned if the alteration was successful.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<synopsis>
ALTER GROUP <replaceable class="PARAMETER">groupname</replaceable> ADD USER <replaceable class="PARAMETER">username</replaceable> [, ... ]
ALTER GROUP <replaceable class="PARAMETER">groupname</replaceable> DROP USER <replaceable class="PARAMETER">username</replaceable> [, ... ]
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-ALTERGROUP-1">
<refsect1info>
<date>2000-01-14</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>ALTER GROUP</command> is used to add or remove users from a
group. Only database superusers can use this command.
Adding a user to a group does not create the user. Similarly, removing
a user from a group does not drop the user itself.
</para>
<para>
Use <xref linkend="SQL-CREATEGROUP" endterm="SQL-CREATEGROUP-title">
to create a new group and <xref linkend="SQL-DROPGROUP"
@ -101,10 +38,48 @@ ALTER GROUP <replaceable class="PARAMETER">name</replaceable> DROP USER <replace
</para>
</refsect1>
<refsect1 id="R1-SQL-ALTERGROUP-2">
<title>
Usage
</title>
<refsect1>
<title>Parameter</title>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">groupname</replaceable></term>
<listitem>
<para>
The name of the group to modify.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">username</replaceable></term>
<listitem>
<para>
Users which are to be added or removed from the group. The users
must exist.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER GROUP</computeroutput></term>
<listitem>
<para>
Message returned if the alteration was successful.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
Add users to a group:
@ -121,24 +96,13 @@ ALTER GROUP workers DROP USER beth;
</para>
</refsect1>
<refsect1 id="R1-SQL-ALTERGROUP-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-ALTERGROUP-4">
<refsect2info>
<date>2000-01-14</date>
</refsect2info>
<title>
SQL92
</title>
<para>
There is no <command>ALTER GROUP</command> statement in
<acronym>SQL92</acronym>. The concept of roles is
similar.
</para>
</refsect2>
<para>
There is no <command>ALTER GROUP</command> statement in the SQL
standard. The concept of roles is similar.
</para>
</refsect1>
</refentry>

530
doc/src/sgml/ref/alter_table.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.58 2003/03/25 16:15:38 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.59 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,19 +8,14 @@ PostgreSQL documentation
<refentrytitle id="sql-altertable-title">ALTER TABLE</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
ALTER TABLE
</refname>
<refpurpose>
change the definition of a table
</refpurpose>
<refname>ALTER TABLE</refname>
<refpurpose>change the definition of a table</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ]
ADD [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> <replaceable class="PARAMETER">type</replaceable> [ <replaceable class="PARAMETER">column_constraint</replaceable> [ ... ] ]
ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ]
@ -48,179 +43,19 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
CLUSTER ON <replaceable class="PARAMETER">index_name</replaceable>
</synopsis>
<refsect2 id="R2-SQL-ALTERTABLE-1">
<refsect2info>
<date>1998-04-15</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER"> table </replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of an existing table to
alter. If <literal>ONLY</> is specified, only that table is
altered. If <literal>ONLY</> is not specified, the table and all
its descendant tables (if any) are updated. <literal>*</> can be
appended to the table name to indicate that descendant tables are
to be scanned, but in the current version, this is the default
behavior. (In releases before 7.1, <literal>ONLY</> was the
default behavior.) The default can be altered by changing the
<option>SQL_INHERITANCE</option> configuration option.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> column </replaceable></term>
<listitem>
<para>
Name of a new or existing column.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> type </replaceable></term>
<listitem>
<para>
Type of the new column.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> new_column </replaceable></term>
<listitem>
<para>
New name for an existing column.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> new_table </replaceable></term>
<listitem>
<para>
New name for the table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> table_constraint </replaceable></term>
<listitem>
<para>
New table constraint for the table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> constraint_name </replaceable></term>
<listitem>
<para>
Name of an existing constraint to drop.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">new_owner </replaceable></term>
<listitem>
<para>
The user name of the new owner of the table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> index_name </replaceable></term>
<listitem>
<para>
The index name on which the table should be marked for clustering.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>CASCADE</term>
<listitem>
<para>
Automatically drop objects that depend on the dropped column
or constraint (for example, views referencing the column).
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>RESTRICT</term>
<listitem>
<para>
Refuse to drop the column or constraint if there are any dependent
objects. This is the default behavior.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-ALTERTABLE-2">
<refsect2info>
<date>1998-04-15</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER TABLE</computeroutput></term>
<listitem>
<para>
Message returned from column or table renaming.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>ERROR</computeroutput></term>
<listitem>
<para>
Message returned if table or column is not available.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-ALTERTABLE-1">
<refsect1info>
<date>1998-04-15</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>ALTER TABLE</command> changes the definition of an existing table.
There are several sub-forms:
</para>
There are several subforms:
<variablelist>
<varlistentry>
<term>ADD COLUMN</term>
<term><literal>ADD COLUMN</literal></term>
<listitem>
<para>
This form adds a new column to the table using the same syntax as
@ -230,45 +65,45 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
</varlistentry>
<varlistentry>
<term>DROP COLUMN</term>
<term><literal>DROP COLUMN</literal></term>
<listitem>
<para>
This form drops a column from a table. Note that indexes and
This form drops a column from a table. Indexes and
table constraints involving the column will be automatically
dropped as well. You will need to say <literal>CASCADE</> if
anything outside the table depends on the column --- for example,
foreign key references, views, etc.
anything outside the table depends on the column, for example,
foreign key references or views.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>SET/DROP DEFAULT</term>
<term><literal>SET</literal>/<literal>DROP DEFAULT</literal></term>
<listitem>
<para>
These forms set or remove the default value for a column. Note
that defaults only apply to subsequent <command>INSERT</command>
These forms set or remove the default value for a column.
The default values only apply to subsequent <command>INSERT</command>
commands; they do not cause rows already in the table to change.
Defaults may also be created for views, in which case they are
inserted into <command>INSERT</> statements on the view before
the view's ON INSERT rule is applied.
the view's <literal>ON INSERT</literal> rule is applied.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>SET/DROP NOT NULL</term>
<term><literal>SET</literal>/<literal>DROP NOT NULL</literal></term>
<listitem>
<para>
These forms change whether a column is marked to allow NULL
values or to reject NULL values. You may only <literal>SET NOT NULL</>
when the table contains no null values in the column.
These forms change whether a column is marked to allow null
values or to reject null values. You can only use <literal>SET
NOT NULL</> when the column contains no null values.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>SET STATISTICS</term>
<term><literal>SET STATISTICS</literal></term>
<listitem>
<para>
This form
@ -281,39 +116,40 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
</varlistentry>
<varlistentry>
<term>SET STORAGE</term>
<term><literal>SET STORAGE</literal></term>
<listitem>
<para>
This form sets the storage mode for a column. This controls whether this
column is held inline or in a supplementary table, and whether the data
should be compressed or not. <literal>PLAIN</literal> must be used
for fixed-length values such as <literal>INTEGER</literal> and is
for fixed-length values such as <type>integer</type> and is
inline, uncompressed. <literal>MAIN</literal> is for inline,
compressible data. <literal>EXTERNAL</literal> is for external,
uncompressed data and <literal>EXTENDED</literal> is for external,
uncompressed data, and <literal>EXTENDED</literal> is for external,
compressed data. <literal>EXTENDED</literal> is the default for all
data types that support it. The use of <literal>EXTERNAL</literal> will
make substring operations on a TEXT column faster, at the penalty of
data types that support it. The use of <literal>EXTERNAL</literal> will, for example,
make substring operations on a <type>text</type> column faster, at the penalty of
increased storage space.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>SET WITHOUT OIDS</term>
<term><literal>SET WITHOUT OIDS</literal></term>
<listitem>
<para>
Removes the <literal>OID</literal> column from the the table. Removing (setting without)
oids from a table also do not occur immediately. The space an <literal>OID</literal>
uses will be reclaimed when the tuple is updated. Without updating the tuple, both the
space and the value of the <literal>OID</literal> are maintained indefinitely. This is
semantically similar to the <literal>DROP COLUMN</literal> process.
This form removes the <literal>oid</literal> column from the
table. Removing OIDs from a table does not occur immediately.
The space that the OID uses will be reclaimed when the row is
updated. Without updating the row, both the space and the value
of the OID are kept indefinitely. This is semantically similar
to the <literal>DROP COLUMN</literal> process.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>RENAME</term>
<term><literal>RENAME</literal></term>
<listitem>
<para>
The <literal>RENAME</literal> forms change the name of a table
@ -324,7 +160,7 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
</varlistentry>
<varlistentry>
<term>ADD <replaceable class="PARAMETER">table_constraint</replaceable></term>
<term><literal>ADD <replaceable class="PARAMETER">table_constraint</replaceable></literal></term>
<listitem>
<para>
This form adds a new constraint to a table using the same syntax as
@ -334,7 +170,7 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
</varlistentry>
<varlistentry>
<term>DROP CONSTRAINT</term>
<term><literal>DROP CONSTRAINT</literal></term>
<listitem>
<para>
This form drops constraints on a table.
@ -346,17 +182,17 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
</varlistentry>
<varlistentry>
<term>OWNER</term>
<term><literal>OWNER</literal></term>
<listitem>
<para>
This form changes the owner of the table, index, sequence or view to the
This form changes the owner of the table, index, sequence, or view to the
specified user.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>CLUSTER</term>
<term><literal>CLUSTER</literal></term>
<listitem>
<para>
This form marks a table for future <xref linkend="SQL-CLUSTER" endterm="sql-cluster-title">
@ -366,27 +202,166 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
</varlistentry>
</variablelist>
</para>
<para>
You must own the table to use <command>ALTER TABLE</>; except for
<command>ALTER TABLE OWNER</>, which may only be executed by a superuser.
</para>
</refsect1>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">table</replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of an existing table to
alter. If <literal>ONLY</> is specified, only that table is
altered. If <literal>ONLY</> is not specified, the table and all
its descendant tables (if any) are updated. <literal>*</> can be
appended to the table name to indicate that descendant tables are
to be altered, but in the current version, this is the default
behavior. (In releases before 7.1, <literal>ONLY</> was the
default behavior. The default can be altered by changing the
configuration parameter <varname>sql_inheritance</varname>.)
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">column</replaceable></term>
<listitem>
<para>
Name of a new or existing column.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">type</replaceable></term>
<listitem>
<para>
Data type of the new column.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">new_column</replaceable></term>
<listitem>
<para>
New name for an existing column.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">new_table</replaceable></term>
<listitem>
<para>
New name for the table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">table_constraint</replaceable></term>
<listitem>
<para>
New table constraint for the table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">constraint_name</replaceable></term>
<listitem>
<para>
Name of an existing constraint to drop.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">new_owner</replaceable></term>
<listitem>
<para>
The user name of the new owner of the table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">index_name</replaceable></term>
<listitem>
<para>
The index name on which the table should be marked for clustering.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>CASCADE</literal></term>
<listitem>
<para>
Automatically drop objects that depend on the dropped column
or constraint (for example, views referencing the column).
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>RESTRICT</literal></term>
<listitem>
<para>
Refuse to drop the column or constraint if there are any dependent
objects. This is the default behavior.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER TABLE</computeroutput></term>
<listitem>
<para>
Message returned if successful.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>ERROR</computeroutput></term>
<listitem>
<para>
Message returned if table or column does not exist.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<refsect2 id="R2-SQL-ALTERTABLE-3">
<refsect2info>
<date>1998-04-15</date>
</refsect2info>
<title>
Notes
</title>
<para>
The keyword <literal>COLUMN</literal> is noise and can be omitted.
The key word <literal>COLUMN</literal> is noise and can be omitted.
</para>
<para>
In the current implementation of <literal>ADD COLUMN</literal>,
default and NOT NULL clauses for the new column are not supported.
The new column always comes into being with all values NULL.
default and <literal>NOT NULL</> clauses for the new column are not supported.
The new column always comes into being with all values null.
You can use the <literal>SET DEFAULT</literal> form
of <command>ALTER TABLE</command> to set the default afterward.
(You may also want to update the already existing rows to the
@ -397,25 +372,25 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable>
</para>
<para>
The <literal>DROP COLUMN</literal> command does not physically remove
The <literal>DROP COLUMN</literal> form does not physically remove
the column, but simply makes it invisible to SQL operations. Subsequent
inserts and updates of the table will store a NULL for the column.
insert and update operations in the table will store a null value for the column.
Thus, dropping a column is quick but it will not immediately reduce the
on-disk size of your table, as the space occupied
by the dropped column is not reclaimed. The space will be
reclaimed over time as existing rows are updated.
To reclaim the space at once, do a dummy <command>UPDATE</> of all rows
and then vacuum, as in:
<programlisting>
<programlisting>
UPDATE table SET col = col;
VACUUM FULL table;
</programlisting>
</programlisting>
</para>
<para>
If a table has any descendant tables, it is not permitted to ADD
or RENAME a column in the parent table without doing the same to
the descendants --- that is, <command>ALTER TABLE ONLY</command>
If a table has any descendant tables, it is not permitted to add
or rename a column in the parent table without doing the same to
the descendants. That is, <command>ALTER TABLE ONLY</command>
will be rejected. This ensures that the descendants always have
columns matching the parent.
</para>
@ -431,126 +406,115 @@ VACUUM FULL table;
</para>
<para>
Changing any part of the schema of a system
catalog is not permitted.
Changing any part of a system catalog table is not permitted.
</para>
<para>
Refer to <command>CREATE TABLE</command> for a further description
of valid arguments. <xref linkend="ddl"> has further information on
of valid parameters. <xref linkend="ddl"> has further information on
inheritance.
</para>
</refsect2>
</refsect1>
<refsect1 id="R1-SQL-ALTERTABLE-2">
<title>
Usage
</title>
<refsect1>
<title>Examples</title>
<para>
To add a column of type <type>varchar</type> to a table:
<programlisting>
ALTER TABLE distributors ADD COLUMN address VARCHAR(30);
</programlisting>
<programlisting>
ALTER TABLE distributors ADD COLUMN address varchar(30);
</programlisting>
</para>
<para>
To drop a column from a table:
<programlisting>
<programlisting>
ALTER TABLE distributors DROP COLUMN address RESTRICT;
</programlisting>
</programlisting>
</para>
<para>
To rename an existing column:
<programlisting>
<programlisting>
ALTER TABLE distributors RENAME COLUMN address TO city;
</programlisting>
</programlisting>
</para>
<para>
To rename an existing table:
<programlisting>
<programlisting>
ALTER TABLE distributors RENAME TO suppliers;
</programlisting>
</programlisting>
</para>
<para>
To add a NOT NULL constraint to a column:
<programlisting>
To add a not-null constraint to a column:
<programlisting>
ALTER TABLE distributors ALTER COLUMN street SET NOT NULL;
</programlisting>
To remove a NOT NULL constraint from a column:
<programlisting>
</programlisting>
To remove a not-null constraint from a column:
<programlisting>
ALTER TABLE distributors ALTER COLUMN street DROP NOT NULL;
</programlisting>
</programlisting>
</para>
<para>
To add a check constraint to a table:
<programlisting>
<programlisting>
ALTER TABLE distributors ADD CONSTRAINT zipchk CHECK (char_length(zipcode) = 5);
</programlisting>
</programlisting>
</para>
<para>
To remove a check constraint from a table and all its children:
<programlisting>
<programlisting>
ALTER TABLE distributors DROP CONSTRAINT zipchk;
</programlisting>
</programlisting>
</para>
<para>
To add a foreign key constraint to a table:
<programlisting>
ALTER TABLE distributors ADD CONSTRAINT distfk FOREIGN KEY (address) REFERENCES addresses(address) MATCH FULL;
</programlisting>
<programlisting>
ALTER TABLE distributors ADD CONSTRAINT distfk FOREIGN KEY (address) REFERENCES addresses (address) MATCH FULL;
</programlisting>
</para>
<para>
To add a (multicolumn) unique constraint to a table:
<programlisting>
<programlisting>
ALTER TABLE distributors ADD CONSTRAINT dist_id_zipcode_key UNIQUE (dist_id, zipcode);
</programlisting>
</programlisting>
</para>
<para>
To add an automatically named primary key constraint to a table, noting
that a table can only ever have one primary key:
<programlisting>
<programlisting>
ALTER TABLE distributors ADD PRIMARY KEY (dist_id);
</programlisting>
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-ALTERTABLE-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-ALTERTABLE-4">
<refsect2info>
<date>1998-04-15</date>
</refsect2info>
<title>SQL92</title>
<para>
The <literal>ADD COLUMN</literal> form is compliant with the exception that
it does not support defaults and NOT NULL constraints, as explained above.
The <literal>ALTER COLUMN</literal> form is in full compliance.
</para>
<para>
The <literal>ADD COLUMN</literal> form conforms with the SQL
standard, with the exception that it does not support defaults and
not-null constraints, as explained above. The <literal>ALTER
COLUMN</literal> form is in full conformance.
</para>
<para>
The clauses to rename tables, columns, indexes, and sequences are
<productname>PostgreSQL</productname> extensions from SQL92.
</para>
<para>
The clauses to rename tables, columns, indexes, views, and sequences are
<productname>PostgreSQL</productname> extensions of the SQL standard.
</para>
<para>
<command>ALTER TABLE DROP COLUMN</> can be used to drop the only column
of a table, leaving a zero-column table. This is an extension from SQL92,
which disallows zero-column tables.
</para>
</refsect2>
<para>
<command>ALTER TABLE DROP COLUMN</> can be used to drop the only
column of a table, leaving a zero-column table. This is an
extension of SQL, which disallows zero-column tables.
</para>
</refsect1>
</refentry>

215
doc/src/sgml/ref/alter_trigger.sgml
View File

@ -1,162 +1,117 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_trigger.sgml,v 1.4 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
<refentry id="SQL-ALTERTRIGGER">
<refmeta>
<refentrytitle id="sql-altertrigger-title">
ALTER TRIGGER
</refentrytitle>
<refentrytitle id="sql-altertrigger-title">ALTER TRIGGER</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
ALTER TRIGGER
</refname>
<refpurpose>
change the definition of a trigger
</refpurpose>
<refname>ALTER TRIGGER</refname>
<refpurpose>change the definition of a trigger</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>2002-04-19</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
ALTER TRIGGER <replaceable class="PARAMETER">trigger</replaceable> ON <replaceable class="PARAMETER">table</replaceable>
RENAME TO <replaceable class="PARAMETER">newname</replaceable>
</synopsis>
<refsect2 id="R2-SQL-ALTERTRIGGER-1">
<refsect2info>
<date>2002-04-19</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER"> trigger </replaceable></term>
<listitem>
<para>
The name of an existing trigger to alter.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> table </replaceable></term>
<listitem>
<para>
The name of the table on which this trigger acts.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER"> newname </replaceable></term>
<listitem>
<para>
New name for the existing trigger.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-ALTERTRIGGER-2">
<refsect2info>
<date>2002-04-19</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER TRIGGER</computeroutput></term>
<listitem>
<para>
Message returned from trigger renaming.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>ERROR</computeroutput></term>
<listitem>
<para>
Message returned if trigger is not available, or new name is a duplicate of another existing trigger on the table.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-ALTERTRIGGER-1">
<refsect1info>
<date>2002-04-19</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>ALTER TRIGGER</command> changes the definition of an existing trigger.
The <literal>RENAME</literal> clause causes the name of a trigger on the given table
to change without otherwise changing the trigger definition.
<command>ALTER TRIGGER</command> changes properties of an existing
trigger. The <literal>RENAME</literal> clause changes the name of
the given trigger without otherwise changing the trigger
definition.
</para>
<para>
You must own the table on which the trigger acts in order to change its properties.
You must own the table on which the trigger acts to be allowed to change its properties.
</para>
<refsect2 id="R2-SQL-ALTERTRIGGER-3">
<refsect2info>
<date>2002-04-19</date>
</refsect2info>
<title>
Notes
</title>
<para>
Refer to <command>CREATE TRIGGER</command> for a further description
of valid arguments.
</para>
</refsect2>
</refsect1>
<refsect1 id="R1-SQL-ALTERTRIGGER-2">
<title>
Usage
</title>
<refsect1>
<title>Parameter</title>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">trigger</replaceable></term>
<listitem>
<para>
The name of an existing trigger to alter.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">table</replaceable></term>
<listitem>
<para>
The name of the table on which this trigger acts.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">newname</replaceable></term>
<listitem>
<para>
The new name for the trigger.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER TRIGGER</computeroutput></term>
<listitem>
<para>
Message returned if successful.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>ERROR</computeroutput></term>
<listitem>
<para>
If the trigger does not exist, or the new name is a duplicate of
another existing trigger on the table.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
To rename an existing trigger:
<programlisting>
<programlisting>
ALTER TRIGGER emp_stamp ON emp RENAME TO emp_track_chgs;
</programlisting>
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-ALTERTRIGGER-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-ALTERTRIGGER-4">
<refsect2info>
<date>2002-04-19</date>
</refsect2info>
<title>SQL92</title>
<para>
<command>ALTER TRIGGER</command> is a <productname>PostgreSQL</>
extension of SQL92.
</para>
</refsect2>
<para>
<command>ALTER TRIGGER</command> is a <productname>PostgreSQL</>
extension of the SQL standard.
</para>
</refsect1>
</refentry>

32
doc/src/sgml/ref/alter_user.sgml
View File

@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_user.sgml,v 1.26 2003/03/25 16:15:39 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_user.sgml,v 1.27 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -20,7 +20,7 @@ ALTER USER <replaceable class="PARAMETER">username</replaceable> [ [ WITH ] <rep
where <replaceable class="PARAMETER">option</replaceable> can be:
[ ENCRYPTED | UNENCRYPTED ] PASSWORD '<replaceable class="PARAMETER">password</replaceable>'
[ ENCRYPTED | UNENCRYPTED ] PASSWORD '<replaceable class="PARAMETER">password</replaceable>'
| CREATEDB | NOCREATEDB
| CREATEUSER | NOCREATEUSER
| VALID UNTIL '<replaceable class="PARAMETER">abstime</replaceable>'
@ -42,8 +42,8 @@ ALTER USER <replaceable class="PARAMETER">username</replaceable> RESET <replacea
<para>
The first variant of this command in the synopsis changes certain
global user privileges and authentication settings. (See below for
details.) Only a database superuser can change privileges and
password expiration with this command. Ordinary users can only
details.) Only a database superuser can change these privileges and
the password expiration with this command. Ordinary users can only
change their own password.
</para>
@ -52,15 +52,15 @@ ALTER USER <replaceable class="PARAMETER">username</replaceable> RESET <replacea
a specified configuration variable. Whenever the user subsequently
starts a new session, the specified value becomes the session default,
overriding whatever setting is present in <filename>postgresql.conf</>
or has been received from the postmaster.
or has been received from the <command>postmaster</command> command line.
Ordinary users can change their own session defaults.
Superusers can change anyone's session defaults.
</para>
</refsect1>
<refsect2>
<title>Parameters</title>
<refsect1>
<title>Parameters</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">username</replaceable></term>
@ -99,8 +99,8 @@ ALTER USER <replaceable class="PARAMETER">username</replaceable> RESET <replacea
<listitem>
<para>
These clauses define a user's ability to create databases. If
<literal>CREATEDB</literal> is specified, the user being
defined will be allowed to create his own databases. Using
<literal>CREATEDB</literal> is specified, the user
will be allowed to create his own databases. Using
<literal>NOCREATEDB</literal> will deny a user the ability to
create databases.
</para>
@ -125,7 +125,7 @@ ALTER USER <replaceable class="PARAMETER">username</replaceable> RESET <replacea
<para>
The date (and, optionally, the time)
at which this user's password is to expire. To set the password
never to expire, use 'infinity'.
never to expire, use <literal>'infinity'</>.
</para>
</listitem>
</varlistentry>
@ -152,14 +152,11 @@ ALTER USER <replaceable class="PARAMETER">username</replaceable> RESET <replacea
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>ALTER USER</computeroutput></term>
@ -175,12 +172,11 @@ ALTER USER <replaceable class="PARAMETER">username</replaceable> RESET <replacea
<listitem>
<para>
Error message returned if the specified user is not known to
the database.
the database system.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1>
@ -226,10 +222,10 @@ ALTER USER manuel VALID UNTIL 'Jan 31 2030';
<para>
Change a user's valid until date, specifying that his
authorization should expire at midday on 4th May 1998 using
authorization should expire at midday on 4th May 2005 using
the time zone which is one hour ahead of <acronym>UTC</>:
<programlisting>
ALTER USER chris VALID UNTIL 'May 4 12:00:00 1998 +1';
ALTER USER chris VALID UNTIL 'May 4 12:00:00 2005 +1';
</programlisting>
</para>

184
doc/src/sgml/ref/analyze.sgml
View File

@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/analyze.sgml,v 1.11 2003/03/25 16:15:39 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/analyze.sgml,v 1.12 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,97 +8,24 @@ PostgreSQL documentation
<refentrytitle id="sql-analyze-title">ANALYZE</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
ANALYZE
</refname>
<refpurpose>
collect statistics about a database
</refpurpose>
<refname>ANALYZE</refname>
<refpurpose>collect statistics about a database</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>2001-05-04</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<replaceable class="PARAMETER">column</replaceable> [, ...] ) ] ]
</synopsis>
<refsect2 id="R2-SQL-ANALYZE-1">
<refsect2info>
<date>2001-05-04</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term>VERBOSE</term>
<listitem>
<para>
Enables display of progress messages.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">table</replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of a specific table to
analyze. Defaults to all tables in the current database.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">column</replaceable></term>
<listitem>
<para>
The name of a specific column to analyze. Defaults to all columns.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-ANALYZE-2">
<refsect2info>
<date>2001-05-04</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
<returnvalue>ANALYZE</returnvalue>
</computeroutput></term>
<listitem>
<para>
The command is complete.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-ANALYZE-1">
<refsect1info>
<date>2001-05-04</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>ANALYZE</command> collects statistics about the contents of
<productname>PostgreSQL</productname> tables, and stores the results in
tables in the database, and stores the results in
the system table <literal>pg_statistic</literal>. Subsequently,
the query planner uses the statistics to help determine the most efficient
execution plans for queries.
@ -108,16 +35,61 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
With no parameter, <command>ANALYZE</command> examines every table in the
current database. With a parameter, <command>ANALYZE</command> examines
only that table. It is further possible to give a list of column names,
in which case only the statistics for those columns are updated.
in which case only the statistics for those columns are collected.
</para>
</refsect1>
<refsect2 id="R2-SQL-ANALYZE-3">
<refsect2info>
<date>2001-05-04</date>
</refsect2info>
<title>
Notes
</title>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><literal>VERBOSE</literal></term>
<listitem>
<para>
Enables display of progress messages.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">table</replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of a specific table to
analyze. Defaults to all tables in the current database.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">column</replaceable></term>
<listitem>
<para>
The name of a specific column to analyze. Defaults to all columns.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>ANALYZE</computeroutput></term>
<listitem>
<para>
The command is complete.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
It is a good idea to run <command>ANALYZE</command> periodically, or
@ -138,7 +110,7 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
<para>
For large tables, <command>ANALYZE</command> takes a random sample of the
table contents, rather than examining every row. This allows even very
large tables to be analyzed in a small amount of time. Note however
large tables to be analyzed in a small amount of time. Note, however,
that the statistics are only approximate, and will change slightly each
time <command>ANALYZE</command> is run, even if the actual table contents
did not change. This may result in small changes in the planner's
@ -159,7 +131,7 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
The extent of analysis can be controlled by adjusting the
<literal>default_statistics_target</> parameter variable, or on a
column-by-column basis by setting the per-column
statistics target with <command>ALTER TABLE ALTER COLUMN SET
statistics target with <command>ALTER TABLE ... ALTER COLUMN ... SET
STATISTICS</command> (see
<xref linkend="sql-altertable" endterm="sql-altertable-title">). The
target value sets the maximum number of entries in the most-common-value
@ -170,7 +142,7 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
in <literal>pg_statistic</literal>.
In particular, setting the statistics target to zero disables collection of
statistics for that column. It may be useful to do that for columns that
are never used as part of the WHERE, GROUP BY, or ORDER BY clauses of
are never used as part of the <literal>WHERE</>, <literal>GROUP BY</>, or <literal>ORDER BY</> clauses of
queries, since the planner will have no use for statistics on such columns.
</para>
@ -180,26 +152,14 @@ ANALYZE [ VERBOSE ] [ <replaceable class="PARAMETER">table</replaceable> [ (<rep
the target causes a proportional increase in the time and space needed
to do <command>ANALYZE</command>.
</para>
</refsect2>
</refsect1>
<refsect1 id="R1-SQL-ANALYZE-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-ANALYZE-4">
<refsect2info>
<date>2001-05-04</date>
</refsect2info>
<title>
SQL92
</title>
<para>
There is no <command>ANALYZE</command> statement in <acronym>SQL92</acronym>.
</para>
</refsect2>
<para>
There is no <command>ANALYZE</command> statement in the SQL standard.
</para>
</refsect1>
</refentry>

301
doc/src/sgml/ref/begin.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/begin.sgml,v 1.22 2003/03/25 16:15:39 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/begin.sgml,v 1.23 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,218 +8,137 @@ PostgreSQL documentation
<refentrytitle id="SQL-BEGIN-TITLE">BEGIN</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
BEGIN
</refname>
<refpurpose>
start a transaction block
</refpurpose>
</refnamediv>
<refname>BEGIN</refname>
<refpurpose>start a transaction block</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
BEGIN [ WORK | TRANSACTION ]
</synopsis>
<refsect2 id="R2-SQL-BEGIN-1">
<refsect2info>
<date>1999-06-11</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term>WORK</term>
<term>TRANSACTION</term>
<listitem>
<para>
Optional keywords. They have no effect.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-BEGIN-2">
<refsect2info>
<date>1999-06-11</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
BEGIN
</computeroutput></term>
<listitem>
<para>
This signifies that a new transaction has been started.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>
WARNING: BEGIN: already a transaction in progress
</computeroutput></term>
<listitem>
<para>
This indicates that a transaction was already in progress.
The current transaction is not affected.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-BEGIN-1">
<refsect1info>
<date>1999-06-11</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
By default, <productname>PostgreSQL</productname> executes transactions
in <firstterm>unchained mode</firstterm>
(also known as <quote>autocommit</quote> in other database
systems).
In other words, each user statement is executed in its own transaction
and a commit is implicitly performed at the end of the statement
(if execution was successful, otherwise a rollback is done).
<command>BEGIN</command> initiates a user transaction in chained mode,
i.e., all user statements after <command>BEGIN</command> command will
be executed in a single transaction until an explicit
<xref linkend="sql-commit" endterm="sql-commit-title"> or
<xref linkend="sql-rollback" endterm="sql-rollback-title">.
Statements are executed more quickly in chained mode,
because transaction start/commit requires significant CPU and disk
activity. Execution of multiple statements inside a transaction
is also useful to ensure consistency when changing several
related tables: other clients will be unable to see the intermediate
states wherein not all the related updates have been done.
</para>
<para>
The default transaction isolation level in
<productname>PostgreSQL</productname>
is READ COMMITTED, wherein each query inside the transaction sees changes
committed before that query begins execution. So, you have to use
<command>SET TRANSACTION ISOLATION LEVEL SERIALIZABLE</command>
just after <command>BEGIN</command> if you need more rigorous transaction
isolation. (Alternatively, you can change the default transaction
isolation level; see <xref linkend="runtime-config"> for details.)
In SERIALIZABLE mode queries will see only changes committed before
the entire
transaction began (actually, before execution of the first <acronym>DML</> statement
in the transaction).
</para>
<para>
Transactions have the standard <acronym>ACID</acronym>
(atomic, consistent, isolatable, and durable) properties.
By default, <productname>PostgreSQL</productname> executes
transactions in <quote>autocommit</quote> mode, that is, each
statement is executed in its own transaction and a commit is
implicitly performed at the end of the statement (if execution was
successful, otherwise a rollback is done).
<command>BEGIN</command> initiates a transaction block, that is,
all statements after <command>BEGIN</command> command will be
executed in a single transaction until an explicit <xref
linkend="sql-commit" endterm="sql-commit-title"> or <xref
linkend="sql-rollback" endterm="sql-rollback-title">. Statements
are executed more quickly in a transaction block, because
transaction start/commit requires significant CPU and disk
activity. Execution of multiple statements inside a transaction is
also useful to ensure consistency when changing several related
tables: other sessions will be unable to see the intermediate states
wherein not all the related updates have been done.
</para>
</refsect1>
<refsect2 id="R2-SQL-BEGIN-3">
<refsect2info>
<date>1999-06-11</date>
</refsect2info>
<title>
Notes
</title>
<para>
<xref linkend="sql-start-transaction"
endterm="sql-start-transaction-title"> has the same functionality
as <command>BEGIN</>.
</para>
<para>
Use <xref linkend="SQL-COMMIT" endterm="SQL-COMMIT-TITLE">
or
<xref linkend="SQL-ROLLBACK" endterm="SQL-ROLLBACK-TITLE">
to terminate a transaction.
</para>
<refsect1>
<title>Parameters</title>
<para>
Refer to <xref linkend="sql-lock" endterm="sql-lock-title">
for further information
about locking tables inside a transaction.
</para>
<variablelist>
<varlistentry>
<term><literal>WORK</literal></term>
<term><literal>TRANSACTION</literal></term>
<listitem>
<para>
Optional key words. They have no effect.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>BEGIN</computeroutput></term>
<listitem>
<para>
This signifies that a new transaction has been started.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>WARNING: BEGIN: already a transaction in progress</computeroutput></term>
<listitem>
<para>
This indicates that a transaction was already in progress. The
current transaction is not affected.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
<xref linkend="sql-start-transaction"
endterm="sql-start-transaction-title"> has the same functionality
as <command>BEGIN</>.
</para>
<para>
If you turn <varname>autocommit</> mode off, then <command>BEGIN</>
is not required: any SQL command automatically starts a transaction.
</para>
</refsect2>
<para>
Use <xref linkend="SQL-COMMIT" endterm="SQL-COMMIT-TITLE"> or
<xref linkend="SQL-ROLLBACK" endterm="SQL-ROLLBACK-TITLE">
to terminate a transaction.
</para>
<para>
If you turn the configuration parameter <varname>autocommit</> off,
then <command>BEGIN</> is not required: any SQL command
automatically starts a transaction.
</para>
</refsect1>
<refsect1 id="R1-SQL-BEGIN-2">
<title>
Usage
</title>
<refsect1>
<title>Examples</title>
<para>
To begin a user transaction:
To begin a transaction block:
<programlisting>
BEGIN WORK;
</programlisting>
<programlisting>
BEGIN;
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-BEGIN-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-BEGIN-4">
<refsect2info>
<date>1999-06-11</date>
</refsect2info>
<title>
SQL92
</title>
<para>
<command>BEGIN</command> is a <productname>PostgreSQL</productname>
language extension. There is no explicit <command>BEGIN</command>
command in the SQL standard; transaction initiation is
always implicit and it terminates either with a
<command>COMMIT</command> or <command>ROLLBACK</command> statement.
</para>
<para>
<command>BEGIN</command>
is a <productname>PostgreSQL</productname> language extension.
There is no explicit <command>BEGIN</command>
command in <acronym>SQL92</acronym>;
transaction initiation is always implicit and it terminates either
with a <command>COMMIT</command> or <command>ROLLBACK</command> statement.
<para>
Other relational database systems may offer an autocommit feature
as a convenience.
</para>
<note>
<para>
Many relational database systems offer an autocommit feature as a
convenience.
</para>
</note>
</para>
<para>
Incidentally, the <literal>BEGIN</literal> keyword is used for a different
purpose in embedded SQL. You are advised to be careful about the transaction
semantics when porting database applications.
</para>
<para>
<acronym>SQL92</acronym> also requires SERIALIZABLE to be the default
transaction isolation level.
</para>
</refsect2>
<para>
Incidentally, the <literal>BEGIN</literal> key word is used for a
different purpose in embedded SQL. You are advised to be careful
about the transaction semantics when porting database applications.
</para>
</refsect1>
</refentry>

6
doc/src/sgml/ref/checkpoint.sgml
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@ -1,4 +1,4 @@
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/checkpoint.sgml,v 1.8 2003/03/25 16:15:39 petere Exp $ -->
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/checkpoint.sgml,v 1.9 2003/04/15 13:25:08 petere Exp $ -->
<refentry id="sql-checkpoint">
<refmeta>
@ -24,8 +24,8 @@ CHECKPOINT
Write-Ahead Logging (WAL) puts a checkpoint in the transaction log
every so often. (To adjust the automatic checkpoint interval, see
the run-time
configuration options <parameter>CHECKPOINT_SEGMENTS</parameter>
and <parameter>CHECKPOINT_TIMEOUT</parameter>.)
configuration options <varname>checkpoint_segments</varname>
and <varname>checkpoint_timeout</varname>.)
The <command>CHECKPOINT</command> command forces an immediate checkpoint
when the command is issued, without waiting for a scheduled checkpoint.
</para>

192
doc/src/sgml/ref/close.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/close.sgml,v 1.13 2002/05/18 15:44:47 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/close.sgml,v 1.14 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,144 +8,104 @@ PostgreSQL documentation
<refentrytitle id="SQL-CLOSE-TITLE">CLOSE</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
CLOSE
</refname>
<refpurpose>
close a cursor
</refpurpose>
<refname>CLOSE</refname>
<refpurpose>close a cursor</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
CLOSE <replaceable class="PARAMETER">cursor</replaceable>
</synopsis>
<refsect2 id="R2-SQL-CLOSE-1">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">cursor</replaceable></term>
<listitem>
<para>
The name of an open cursor to close.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-CLOSE-2">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
CLOSE CURSOR
</computeroutput></term>
<listitem>
<para>
Message returned if the cursor is successfully closed.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>
WARNING: PerformPortalClose: portal "<replaceable class="PARAMETER">cursor</replaceable>" not found
</computeroutput></term>
<listitem>
<para>
This warning is given if
<replaceable class="PARAMETER">cursor</replaceable> is not
declared or has already been closed.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-CLOSE-1">
<refsect1info>
<date>1998-09-08</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>CLOSE</command> frees the resources associated with an open cursor.
After the cursor is closed, no subsequent operations
are allowed on it. A cursor should be closed when it is
no longer needed.
</para>
<para>
An implicit close is executed for every open cursor when a
transaction is terminated by <command>COMMIT</command>
or <command>ROLLBACK</command>.
Every open cursor is implicitly closed when a transaction is
terminated by <command>COMMIT</command> or
<command>ROLLBACK</command>.
</para>
</refsect1>
<refsect2 id="R2-SQL-CLOSE-3">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Notes
</title>
<para>
<productname>PostgreSQL</productname> does not have
an explicit <command>OPEN</command> cursor statement;
a cursor is considered open when it is declared.
Use the <command>DECLARE</command> statement to declare a cursor.
</para>
</refsect2>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">cursor</replaceable></term>
<listitem>
<para>
The name of an open cursor to close.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>CLOSE CURSOR</computeroutput></term>
<listitem>
<para>
Message returned if the cursor is successfully closed.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>WARNING: PerformPortalClose: portal "<replaceable class="PARAMETER">cursor</replaceable>" not found</computeroutput></term>
<listitem>
<para>
This warning is given if <replaceable
class="PARAMETER">cursor</replaceable> is not declared or has
already been closed.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="R1-SQL-CLOSE-2">
<title>
Usage
</title>
<refsect1>
<title>Notes</title>
<para>
<productname>PostgreSQL</productname> does not have an explicit
<command>OPEN</command> cursor statement; a cursor is considered
open when it is declared. Use the <command>DECLARE</command>
statement to declare a cursor.
</para>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
Close the cursor <literal>liahona</literal>:
</para>
<programlisting>
<programlisting>
CLOSE liahona;
</programlisting>
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-CLOSE-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-CLOSE-4">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
SQL92
</title>
<para>
<command>CLOSE</command> is fully compatible with SQL92.
</para>
</refsect2>
<para>
<command>CLOSE</command> is fully conforming with the SQL standard.
</para>
</refsect1>
</refentry>

230
doc/src/sgml/ref/cluster.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/cluster.sgml,v 1.25 2003/03/25 16:15:39 petere Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/cluster.sgml,v 1.26 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,89 +8,27 @@ PostgreSQL documentation
<refentrytitle id="sql-cluster-title">CLUSTER</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
CLUSTER
</refname>
<refpurpose>
cluster a table according to an index
</refpurpose>
<refname>CLUSTER</refname>
<refpurpose>cluster a table according to an index</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
CLUSTER <replaceable class="PARAMETER">indexname</replaceable> ON <replaceable class="PARAMETER">tablename</replaceable>
CLUSTER <replaceable class="PARAMETER">tablename</replaceable>
CLUSTER
</synopsis>
<refsect2 id="R2-SQL-CLUSTER-1">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Inputs
</title>
<para>
</para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">indexname</replaceable></term>
<listitem>
<para>
The name of an index.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">table</replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of a table.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect2>
<refsect2 id="R2-SQL-CLUSTER-2">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
CLUSTER
</computeroutput></term>
<listitem>
<para>
The clustering was done successfully.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-CLUSTER-1">
<refsect1info>
<date>1998-09-08</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>CLUSTER</command> instructs <productname>PostgreSQL</productname>
to cluster the table specified
by <replaceable class="parameter">table</replaceable>
by <replaceable class="parameter">tablename</replaceable>
based on the index specified by
<replaceable class="parameter">indexname</replaceable>. The index must
already have been defined on
@ -102,19 +40,19 @@ CLUSTER
based on the index information. Clustering is a one-time operation:
when the table is subsequently updated, the changes are
not clustered. That is, no attempt is made to store new or
updated tuples according to their index order. If one wishes, one can
periodically re-cluster by issuing the command again.
updated rows according to their index order. If one wishes, one can
periodically recluster by issuing the command again.
</para>
<para>
When a table is clustered, <productname>PostgreSQL</productname>
remembers on which index it was clustered. The form
<command>CLUSTER <replaceable class="parameter">tablename</replaceable></command>,
re-clusters the table on the same index that it was clustered before.
reclusters the table on the same index that it was clustered before.
</para>
<para>
<command>CLUSTER</command> without any parameter re-clusters all the tables
<command>CLUSTER</command> without any parameter reclusters all the tables
in the
current database that the calling user owns, or all tables if called
by a superuser. (Never-clustered tables are not included.) This
@ -129,33 +67,62 @@ CLUSTER
table until the <command>CLUSTER</command> is finished. See
<xref linkend="explicit-locking"> for more information on database locking.
</para>
</refsect1>
<refsect2 id="R2-SQL-CLUSTER-3">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Notes
</title>
<refsect1>
<title>Parameter</title>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">indexname</replaceable></term>
<listitem>
<para>
The name of an index.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">tablename</replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of a table.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>CLUSTER</computeroutput></term>
<listitem>
<para>
The clustering was done successfully.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
In cases where you are accessing single rows randomly
within a table, the actual order of the data in the heap
within a table, the actual order of the data in the
table is unimportant. However, if you tend to access some
data more than others, and there is an index that groups
them together, you will benefit from using <command>CLUSTER</command>.
</para>
<para>
Another place where <command>CLUSTER</command> is helpful is in
cases where you use an
index to pull out several rows from a table. If you are
requesting a range of indexed values from a table, or a
If you are requesting a range of indexed values from a table, or a
single indexed value that has multiple rows that match,
<command>CLUSTER</command> will help because once the index identifies the
heap page for the first row that matches, all other rows
that match are probably already on the same heap page,
saving disk accesses and speeding up the query.
and so you save disk accesses and speed up the query.
</para>
<para>
@ -166,23 +133,17 @@ CLUSTER
sizes.
</para>
<para>
<command>CLUSTER</command> preserves <command>GRANT</command>,
inheritance, index, foreign key, and other ancillary information
about the table.
</para>
<para>
Because <command>CLUSTER</command> remembers the clustering information,
one can cluster the tables one wants clustered manually the first time, and
setup a timed event similar to <command>VACUUM</command> so that the tables
are periodically re-clustered.
are periodically reclustered.
</para>
<para>
Because the optimizer records statistics about the ordering of tables, it
Because the planner records statistics about the ordering of tables, it
is advisable to run <command>ANALYZE</command> on the newly clustered
table. Otherwise, the optimizer may make poor choices of query plans.
table. Otherwise, the planner may make poor choices of query plans.
</para>
<para>
@ -196,68 +157,57 @@ CLUSTER
but the majority of a big table will not fit in the cache.)
The other way to cluster a table is to use
<programlisting>
SELECT <replaceable class="parameter">columnlist</replaceable> INTO TABLE <replaceable class="parameter">newtable</replaceable>
FROM <replaceable class="parameter">table</replaceable> ORDER BY <replaceable class="parameter">columnlist</replaceable>
</programlisting>
<programlisting>
CREATE TABLE <replaceable class="parameter">newtable</replaceable> AS
SELECT <replaceable class="parameter">columnlist</replaceable> FROM <replaceable class="parameter">table</replaceable> ORDER BY <replaceable class="parameter">columnlist</replaceable>;
</programlisting>
which uses the <productname>PostgreSQL</productname> sorting code in
the ORDER BY clause to create the desired order; this is usually much
the <literal>ORDER BY</literal> clause to create the desired order; this is usually much
faster than an index scan for
unordered data. You then drop the old table, use
<command>ALTER TABLE...RENAME</command>
<command>ALTER TABLE ... RENAME</command>
to rename <replaceable class="parameter">newtable</replaceable> to the old name, and
recreate the table's indexes. However, this approach does not preserve
OIDs, constraints, foreign key relationships, granted privileges, and
other ancillary properties of the table --- all such items must be
manually recreated.
</para>
</refsect2>
</refsect1>
<refsect1 id="R1-SQL-CLUSTER-2">
<title>
Usage
</title>
<refsect1>
<title>Examples</title>
<para>
Cluster the <literal>employees</literal> relation on the basis of
its ID attribute:
</para>
<programlisting>
Cluster the table <literal>employees</literal> on the basis of
its index <literal>emp_ind</literal>:
<programlisting>
CLUSTER emp_ind ON emp;
</programlisting>
</programlisting>
</para>
<para>
Cluster the <literal>employees</literal> relation using the same
index that was used before:
</para>
<programlisting>
<programlisting>
CLUSTER emp;
</programlisting>
</programlisting>
</para>
<para>
Cluster all the tables on the database that have previously been clustered:
</para>
<programlisting>
<programlisting>
CLUSTER;
</programlisting>
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-CLUSTER-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-CLUSTER-4">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
SQL92
</title>
<para>
There is no <command>CLUSTER</command> statement in SQL92.
</para>
</refsect2>
<para>
There is no <command>CLUSTER</command> statement in the SQL standard.
</para>
</refsect1>
<refsect1>

220
doc/src/sgml/ref/comment.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/comment.sgml,v 1.20 2002/07/12 18:43:12 tgl Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/comment.sgml,v 1.21 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,21 +8,16 @@ PostgreSQL documentation
<refentrytitle id="SQL-COMMENT-TITLE">COMMENT</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
COMMENT
</refname>
<refpurpose>
define or change the comment of an object
</refpurpose>
<refname>COMMENT</refname>
<refpurpose>define or change the comment of an object</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
COMMENT ON
[
{
TABLE <replaceable class="PARAMETER">object_name</replaceable> |
COLUMN <replaceable class="PARAMETER">table_name</replaceable>.<replaceable class="PARAMETER">column_name</replaceable> |
AGGREGATE <replaceable class="PARAMETER">agg_name</replaceable> (<replaceable class="PARAMETER">agg_type</replaceable>) |
@ -38,83 +33,21 @@ COMMENT ON
TRIGGER <replaceable class="PARAMETER">trigger_name</replaceable> ON <replaceable class="PARAMETER">table_name</replaceable> |
TYPE <replaceable class="PARAMETER">object_name</replaceable> |
VIEW <replaceable class="PARAMETER">object_name</replaceable>
] IS <replaceable class="PARAMETER">'text'</replaceable>
</synopsis>
<refsect2 id="R2-SQL-COMMENT-1">
<refsect2info>
<date>1999-10-25</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="PARAMETER">object_name,
table_name.column_name, agg_name, constraint_name, func_name, op, rule_name, trigger_name</replaceable></term>
<listitem>
<para>
The name of the object to be be commented. Names of tables,
aggregates, domains, functions, indexes, operators, sequences, types,
and views
may be schema-qualified.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">text</replaceable></term>
<listitem>
<para>
The comment to add.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-COMMENT-2">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
COMMENT
</computeroutput></term>
<listitem>
<para>
Message returned if the table is successfully commented.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
} IS <replaceable class="PARAMETER">'text'</replaceable>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-COMMENT-1">
<refsect1info>
<date>1998-10-25</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>COMMENT</command> stores a comment about a database object.
Comments can be
easily retrieved with <command>psql</command>'s
<command>\dd</command>, <command>\d+</command>, or <command>\l+</command>
commands. Other user interfaces to retrieve comments can be built atop
the same built-in functions that <command>psql</command> uses, namely
<function>obj_description()</> and <function>col_description()</>.
easily retrieved with the <application>psql</application> commands
<command>\dd</command>, <command>\d+</command>, and <command>\l+</command>.
Other user interfaces to retrieve comments can be built atop
the same built-in functions that <application>psql</application> uses, namely
<function>obj_description</> and <function>col_description</>.
</para>
<para>
@ -124,75 +57,114 @@ COMMENT
string.
Comments are automatically dropped when the object is dropped.
</para>
<note>
<para>
There is presently no security mechanism
for comments: any user connected to a database can see all the comments
for objects in that database (although only superusers can change
comments for objects that they don't own). Therefore, don't put
security-critical information in comments.
</para>
</note>
</refsect1>
<refsect1 id="R1-SQL-COMMENT-2">
<title>
Usage
</title>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><replaceable class="parameter">object_name</replaceable></term>
<term><replaceable class="parameter">table_name.column_name</replaceable></term>
<term><replaceable class="parameter">aggname</replaceable></term>
<term><replaceable class="parameter">constraint_name</replaceable></term>
<term><replaceable class="parameter">func_name</replaceable></term>
<term><replaceable class="parameter">op</replaceable></term>
<term><replaceable class="parameter">rule_name</replaceable></term>
<term><replaceable class="parameter">trigger_name</replaceable></term>
<listitem>
<para>
The name of the object to be be commented. Names of tables,
aggregates, domains, functions, indexes, operators, sequences,
types, and views may be schema-qualified.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">text</replaceable></term>
<listitem>
<para>
The new comment.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>COMMENT</computeroutput></term>
<listitem>
<para>
Message returned if the comment was successfully changed.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
There is presently no security mechanism for comments: any user
connected to a database can see all the comments for objects in
that database (although only superusers can change comments for
objects that they don't own). Therefore, don't put
security-critical information in comments.
</para>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
Attach a comment to the table <literal>mytable</literal>:
<programlisting>
<programlisting>
COMMENT ON TABLE mytable IS 'This is my table.';
</programlisting>
</programlisting>
Remove it again:
<programlisting>
<programlisting>
COMMENT ON TABLE mytable IS NULL;
</programlisting>
</programlisting>
</para>
<para>
Some more examples:
<programlisting>
<programlisting>
COMMENT ON AGGREGATE my_aggregate (double precision) IS 'Computes sample variance';
COMMENT ON COLUMN my_table.my_field IS 'Employee ID number';
COMMENT ON COLUMN my_table.my_column IS 'Employee ID number';
COMMENT ON DATABASE my_database IS 'Development Database';
COMMENT ON DOMAIN my_domain IS 'Email Address Domain';
COMMENT ON FUNCTION my_function (timestamp) IS 'Returns Roman Numeral';
COMMENT ON INDEX my_index IS 'Enforces uniqueness on employee id';
COMMENT ON INDEX my_index IS 'Enforces uniqueness on employee ID';
COMMENT ON OPERATOR ^ (text, text) IS 'Performs intersection of two texts';
COMMENT ON OPERATOR ^ (NONE, text) IS 'This is a prefix operator on text';
COMMENT ON RULE my_rule ON my_table IS 'Logs UPDATES of employee records';
COMMENT ON RULE my_rule ON my_table IS 'Logs updates of employee records';
COMMENT ON SCHEMA my_schema IS 'Departmental data';
COMMENT ON SEQUENCE my_sequence IS 'Used to generate primary keys';
COMMENT ON TABLE my_schema.my_table IS 'Employee Information';
COMMENT ON TRIGGER my_trigger ON my_table IS 'Used for R.I.';
COMMENT ON TYPE complex IS 'Complex Number datatype';
COMMENT ON TRIGGER my_trigger ON my_table IS 'Used for RI';
COMMENT ON TYPE complex IS 'Complex number data type';
COMMENT ON VIEW my_view IS 'View of departmental costs';
</programlisting>
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-COMMENT-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-COMMENT-4">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
SQL92
</title>
<para>
There is no <command>COMMENT</command> in <acronym>SQL92</acronym>.
</para>
</refsect2>
<para>
There is no <command>COMMENT</command> command in the SQL standard.
</para>
</refsect1>
</refentry>

185
doc/src/sgml/ref/commit.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/commit.sgml,v 1.14 2002/04/21 19:02:39 thomas Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/commit.sgml,v 1.15 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,141 +8,96 @@ PostgreSQL documentation
<refentrytitle id="SQL-COMMIT-TITLE">COMMIT</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
COMMIT
</refname>
<refpurpose>
commit the current transaction
</refpurpose>
<refname>COMMIT</refname>
<refpurpose>commit the current transaction</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-07-20</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
COMMIT [ WORK | TRANSACTION ]
</synopsis>
<refsect2 id="R2-SQL-COMMIT-1">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term>WORK</term>
<term>TRANSACTION</term>
<listitem>
<para>
Optional keywords. They have no effect.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-COMMIT-2">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
COMMIT
</computeroutput></term>
<listitem>
<para>
Message returned if the transaction is successfully committed.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>
WARNING: COMMIT: no transaction in progress
</computeroutput></term>
<listitem>
<para>
If there is no transaction in progress.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-COMMIT-1">
<refsect1info>
<date>1998-09-08</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>COMMIT</command> commits the current transaction. All
changes made by the transaction become visible to others
and are guaranteed to be durable if a crash occurs.
</para>
</refsect1>
<refsect2 id="R2-SQL-COMMIT-3">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Notes
</title>
<para>
The keywords WORK and TRANSACTION are noise and can be omitted.
</para>
<refsect1>
<title>Parameters</title>
<para>
Use <xref linkend="SQL-ROLLBACK" endterm="SQL-ROLLBACK-TITLE">
to abort a transaction.
</para>
</refsect2>
<variablelist>
<varlistentry>
<term><literal>WORK</literal></term>
<term><literal>TRANSACTION</literal></term>
<listitem>
<para>
Optional key words. They have no effect.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>COMMIT</computeroutput></term>
<listitem>
<para>
Message returned if the transaction was successfully committed.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>WARNING: COMMIT: no transaction in progress</computeroutput></term>
<listitem>
<para>
Message if there is no transaction in progress.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="R1-SQL-COMMIT-2">
<title>
Usage
</title>
<refsect1>
<title>Notes</title>
<para>
To make all changes permanent:
<programlisting>
COMMIT WORK;
</programlisting>
Use <xref linkend="SQL-ROLLBACK" endterm="SQL-ROLLBACK-TITLE"> to
abort a transaction.
</para>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
To commit the current transaction and make all changes permanent:
<programlisting>
COMMIT;
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-COMMIT-3">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-COMMIT-4">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
SQL92
</title>
<para>
<acronym>SQL92</acronym> only specifies the two forms <literal>COMMIT</literal>
and <literal>COMMIT WORK</literal>. Otherwise full compatibility.
</para>
</refsect2>
<para>
The SQL standard only specifies the two forms
<literal>COMMIT</literal> and <literal>COMMIT
WORK</literal>. Otherwise, this command is fully conforming.
</para>
</refsect1>
</refentry>

629
doc/src/sgml/ref/copy.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/copy.sgml,v 1.41 2003/03/27 16:51:27 momjian Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/copy.sgml,v 1.42 2003/04/15 13:25:08 petere Exp $
PostgreSQL documentation
-->
@ -8,186 +8,35 @@ PostgreSQL documentation
<refentrytitle id="sql-copy-title">COPY</refentrytitle>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>
COPY
</refname>
<refpurpose>
copy data between files and tables
</refpurpose>
<refname>COPY</refname>
<refpurpose>copy data between files and tables</refpurpose>
</refnamediv>
<refsynopsisdiv>
<refsynopsisdivinfo>
<date>1999-12-11</date>
</refsynopsisdivinfo>
<synopsis>
<synopsis>
COPY <replaceable class="parameter">table</replaceable> [ ( <replaceable class="parameter">column</replaceable> [, ...] ) ]
FROM { '<replaceable class="parameter">filename</replaceable>' | <filename>stdin</filename> }
FROM { '<replaceable class="parameter">filename</replaceable>' | STDIN }
[ [ WITH ]
[ BINARY ]
[ OIDS ]
[ DELIMITER [ AS ] '<replaceable class="parameter">delimiter</replaceable>' ]
[ NULL [ AS ] '<replaceable class="parameter">null string</replaceable>' ] ]
COPY <replaceable class="parameter">table</replaceable> [ ( <replaceable class="parameter">column</replaceable> [, ...] ) ]
TO { '<replaceable class="parameter">filename</replaceable>' | <filename>stdout</filename> }
TO { '<replaceable class="parameter">filename</replaceable>' | STDOUT }
[ [ WITH ]
[ BINARY ]
[ OIDS ]
[ DELIMITER [ AS ] '<replaceable class="parameter">delimiter</replaceable>' ]
[ NULL [ AS ] '<replaceable class="parameter">null string</replaceable>' ] ]
</synopsis>
<refsect2 id="R2-SQL-COPY-1">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Inputs
</title>
<para>
<variablelist>
<varlistentry>
<term><replaceable class="parameter">table</replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of an existing table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">column</replaceable></term>
<listitem>
<para>
An optional list of columns to be copied. If no column list is
specified, all columns will be used.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">filename</replaceable></term>
<listitem>
<para>
The absolute Unix path name of the input or output file.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><filename>stdin</filename></term>
<listitem>
<para>
Specifies that input comes from the client application.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><filename>stdout</filename></term>
<listitem>
<para>
Specifies that output goes to the client application.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>BINARY</term>
<listitem>
<para>
Changes the behavior of field formatting, forcing all data to be
stored or read in binary format rather than as text. You can not
specify <option>DELIMITER</option> or <option>NULL</option>
in binary mode.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>OIDS</term>
<listitem>
<para>
Specifies copying the internal object id (OID) for each row.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">delimiter</replaceable></term>
<listitem>
<para>
The single character that separates fields within each row (line) of the file.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">null string</replaceable></term>
<listitem>
<para>
The string that represents a NULL value. The default is
<quote><literal>\N</literal></quote> (backslash-N). You might
prefer an empty string, for example.
</para>
<note>
<para>
On a <command>COPY FROM</command>, any data item that matches
this string will be stored as a NULL value, so you should
make sure that you use the same string as you used with
<command>COPY TO</command>.
</para>
</note>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
<refsect2 id="R2-SQL-COPY-2">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
Outputs
</title>
<para>
<variablelist>
<varlistentry>
<term><computeroutput>
COPY
</computeroutput></term>
<listitem>
<para>
The copy completed successfully.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><computeroutput>
ERROR: <replaceable>reason</replaceable>
</computeroutput></term>
<listitem>
<para>
The copy failed for the reason stated in the error message.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect2>
</synopsis>
</refsynopsisdiv>
<refsect1 id="R1-SQL-COPY-1">
<refsect1info>
<date>2001-01-02</date>
</refsect1info>
<title>
Description
</title>
<refsect1>
<title>Description</title>
<para>
<command>COPY</command> moves data between
<productname>PostgreSQL</productname> tables and standard file-system
@ -207,61 +56,186 @@ ERROR: <replaceable>reason</replaceable>
<para>
<command>COPY</command> with a file name instructs the
<productname>PostgreSQL</productname> backend to directly read from
or write to a file. The file must be accessible to the backend and
the name must be specified from the viewpoint of the backend. When
<filename>stdin</filename> or <filename>stdout</filename> is
<productname>PostgreSQL</productname> server to directly read from
or write to a file. The file must be accessible to the server and
the name must be specified from the viewpoint of the server. When
<literal>STDIN</literal> or <literal>STDOUT</literal> is
specified, data is transmitted via the connection between the
client frontend and the backend.
<tip>
<para>
Do not confuse <command>COPY</command> with the
<application>psql</application> instruction
<command>\copy</command>. <command>\copy</command> invokes
<command>COPY FROM stdin</command> or <command>COPY TO
stdout</command>, and then fetches/stores the data in a file
accessible to the <application>psql</application> client. Thus,
file accessibility and access rights depend on the client rather
than the backend when <command>\copy</command> is used.
</para>
</tip>
</para>
client and the server.
</para>
</refsect1>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><replaceable class="parameter">table</replaceable></term>
<listitem>
<para>
The name (possibly schema-qualified) of an existing table.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">column</replaceable></term>
<listitem>
<para>
An optional list of columns to be copied. If no column list is
specified, all columns will be used.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">filename</replaceable></term>
<listitem>
<para>
The absolute path name of the input or output file.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>STDIN</literal></term>
<listitem>
<para>
Specifies that input comes from the client application.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>STDOUT</literal></term>
<listitem>
<para>
Specifies that output goes to the client application.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>BINARY</literal></term>
<listitem>
<para>
Forces all data to be stored or read in binary format rather
than as text. You cannot specify the <option>DELIMITER</option>
or <option>NULL</option> options in binary mode.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>OIDS</literal></term>
<listitem>
<para>
Specifies copying the OID for each row. (An error is raised if
<literal>OIDS</literal> is specified for a table that does not
have OIDs.)
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">delimiter</replaceable></term>
<listitem>
<para>
The single character that separates columns within each row
(line) of the file. The default is a tab character.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">null string</replaceable></term>
<listitem>
<para>
The string that represents a null value. The default is
<literal>\N</literal> (backslash-N). You might prefer an empty
string, for example.
</para>
<note>
<para>
On a <command>COPY FROM</command>, any data item that matches
this string will be stored as a null value, so you should make
sure that you use the same string as you used with
<command>COPY TO</command>.
</para>
</note>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Diagnostics</title>
<variablelist>
<varlistentry>
<term><computeroutput>COPY</computeroutput></term>
<listitem>
<para>
The copy operation completed successfully.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<refsect2 id="R2-SQL-COPY-3">
<refsect2info>
<date>2001-01-02</date>
</refsect2info>
<title>
Notes
</title>
<para>
<command>COPY</command> can only be used with plain tables, not
with views.
</para>
<para>
The BINARY keyword will force all data to be
The <literal>BINARY</literal> key word will force all data to be
stored/read as binary format rather than as text. It is
somewhat faster than the normal copy command, but a binary copy
somewhat faster than the normal text mode, but a binary format
file is not portable across machine architectures.
</para>
<para>
By default, a text copy uses a tab ("\t") character as a delimiter
between fields. The field delimiter may be changed to any other
single character with the keyword <option>DELIMITER</option>. Characters
in data fields that happen to match the delimiter character will be
backslash quoted.
</para>
<para>
You must have <firstterm>select privilege</firstterm> on any table
You must have select privilege on any table
whose values are read by <command>COPY TO</command>, and
<firstterm>insert privilege</firstterm> on a table into which values
are being inserted by <command>COPY FROM</command>. The backend also
needs appropriate Unix permissions for any file read or written by
<command>COPY</command>.
insert privilege on a table into which values
are being inserted by <command>COPY FROM</command>.
</para>
<para>
Files named in a <command>COPY</command> command are read or written
directly by the server, not by the client application. Therefore,
they must reside on or be accessible to the database server machine,
not the client. They must be accessible to and readable or writable
by the <application>PostgreSQL</application> user (the user ID the
server runs as), not the client. <command>COPY</command> naming a
file is only allowed to database superusers, since it allows reading
or writing any file that the server has privileges to access.
</para>
<para>
Do not confuse <command>COPY</command> with the
<application>psql</application> instruction
<command>\copy</command>. <command>\copy</command> invokes
<command>COPY FROM STDIN</command> or <command>COPY TO
STDOUT</command>, and then fetches/stores the data in a file
accessible to the <application>psql</application> client. Thus,
file accessibility and access rights depend on the client rather
than the server when <command>\copy</command> is used.
</para>
<para>
It is recommended that the file name used in <command>COPY</command>
always be specified as an absolute path. This is enforced by the
server in the case of <command>COPY TO</command>, but for
<command>COPY FROM</command> you do have the option of reading from
a file specified by a relative path. The path will be interpreted
relative to the working directory of the server process (somewhere below
the data directory), not the client's working directory.
</para>
<para>
@ -272,87 +246,52 @@ ERROR: <replaceable>reason</replaceable>
<para>
<command>COPY</command> stops operation at the first error. This
should not lead to problems in the event of a <command>COPY
TO</command>, but the target relation will already have received
TO</command>, but the target table will already have received
earlier rows in a <command>COPY FROM</command>. These rows will not
be visible or accessible, but they still occupy disk space. This may
amount to a considerable amount of wasted disk space if the failure
happened well into a large copy operation. You may wish to invoke
<command>VACUUM</command> to recover the wasted space.
</para>
<para>
Files named in a <command>COPY</command> command are read or written
directly by the backend, not by the client application. Therefore,
they must reside on or be accessible to the database server machine,
not the client. They must be accessible to and readable or writable
by the <application>PostgreSQL</application> user (the user ID the
server runs as), not the client. <command>COPY</command> naming a
file is only allowed to database superusers, since it allows reading
or writing any file that the backend has privileges to access.
<tip>
<para>
The
<application>psql</application> instruction <command>\copy</command>
reads or writes files on the client machine with the client's
permissions, so it is not restricted to superusers.
</para>
</tip>
</para>
<para>
It is recommended that the file name used in <command>COPY</command>
always be specified as an absolute path. This is enforced by the
backend in the case of <command>COPY TO</command>, but for
<command>COPY FROM</command> you do have the option of reading from
a file specified by a relative path. The path will be interpreted
relative to the backend's working directory (somewhere below
<filename>$PGDATA</filename>), not the client's working directory.
</para>
</refsect2>
</refsect1>
<refsect1 id="R1-SQL-COPY-2">
<refsect1info>
<date>2001-01-02</date>
</refsect1info>
<refsect1>
<title>File Formats</title>
<refsect2>
<refsect2info>
<date>2002-02-12</date>
</refsect2info>
<title>Text Format</title>
<para>
When <command>COPY</command> is used without the BINARY option,
the file read or written is a text file with one line per table row.
Columns (attributes) in a row are separated by the delimiter character.
The attribute values themselves are strings generated by the
When <command>COPY</command> is used without the <literal>BINARY</literal> option,
the data read or written is a text file with one line per table row.
Columns in a row are separated by the delimiter character.
The column values themselves are strings generated by the
output function, or acceptable to the input function, of each
attribute's data type. The specified null-value string is used in
place of attributes that are NULL.
place of columns that are null.
<command>COPY FROM</command> will raise an error if any line of the
input file contains more or fewer columns than are expected.
If <literal>OIDS</literal> is specified, the OID is read or written as the first column,
preceding the user data columns.
</para>
<para>
If OIDS is specified, the OID is read or written as the first column,
preceding the user data columns. (An error is raised if OIDS is
specified for a table that does not have OIDs.)
</para>
<para>
End of data can be represented by a single line containing just
backslash-period (<literal>\.</>). An end-of-data marker is
not necessary when reading from a Unix file, since the end of file
not necessary when reading from a file, since the end of file
serves perfectly well; but an end marker must be provided when copying
data to or from a client application.
</para>
<para>
Backslash characters (<literal>\</>) may be used in the
<command>COPY</command> data to quote data characters that might
otherwise be taken as row or column delimiters. In particular, the
following characters <emphasis>must</> be preceded by a backslash if
they appear as part of an attribute value: backslash itself,
they appear as part of a column value: backslash itself,
newline, and the current delimiter character.
</para>
<para>
The following special backslash sequences are recognized by
<command>COPY FROM</command>:
@ -404,47 +343,44 @@ ERROR: <replaceable>reason</replaceable>
backslash sequence, but it does use the other sequences listed above
for those control characters.
</para>
<para>
Never put a backslash before a data character <literal>N</> or period
(<literal>.</>). Such pairs will be mistaken for the default null string
or the end-of-data marker, respectively. Any other backslashed character
that is not mentioned in the above table will be taken to represent itself.
</para>
<para>
It is strongly recommended that applications generating COPY data convert
data newlines and carriage returns to the <literal>\n</> and
<literal>\r</> sequences respectively. At present
(<productname>PostgreSQL</productname> 7.2 and older versions) it is
<literal>\r</> sequences respectively. At present it is
possible to represent a data carriage return without any special quoting,
and to represent a data newline by a backslash and newline. However,
these representations will not be accepted by default in future releases.
</para>
<para>
Note that the end of each row is marked by a Unix-style newline
("\n"). Presently, <command>COPY FROM</command> will not behave as
(<quote><literal>\n</></>). Presently, <command>COPY FROM</command> will not behave as
desired if given a file containing DOS- or Mac-style newlines.
This is expected to change in future releases.
</para>
</refsect2>
<refsect2>
<refsect2info>
<date>2001-01-02</date>
</refsect2info>
<title>Binary Format</title>
<para>
The file format used for <command>COPY BINARY</command> changed in
<application>PostgreSQL</application> v7.1. The new format consists
of a file header, zero or more tuples, and a file trailer.
<application>PostgreSQL</application> 7.1. The new format consists
of a file header, zero or more tuples containing the row data, and
a file trailer.
</para>
<refsect3>
<refsect3info>
<date>2001-01-02</date>
</refsect3info>
<title>
File Header
</title>
<title>File Header</title>
<para>
The file header consists of 24 bytes of fixed fields, followed
by a variable-length header extension area. The fixed fields are:
@ -454,11 +390,11 @@ ERROR: <replaceable>reason</replaceable>
<term>Signature</term>
<listitem>
<para>
12-byte sequence <literal>PGBCOPY\n\377\r\n\0</> --- note that the null
12-byte sequence <literal>PGBCOPY\n\377\r\n\0</> --- note that the zero byte
is a required part of the signature. (The signature is designed to allow
easy identification of files that have been munged by a non-8-bit-clean
transfer. This signature will be changed by newline-translation
filters, dropped nulls, dropped high bits, or parity changes.)
filters, dropped zero bytes, dropped high bits, or parity changes.)
</para>
</listitem>
</varlistentry>
@ -467,7 +403,7 @@ filters, dropped nulls, dropped high bits, or parity changes.)
<term>Integer layout field</term>
<listitem>
<para>
int32 constant 0x01020304 in source's byte order. Potentially, a reader
32-bit integer constant 0x01020304 in source's byte order. Potentially, a reader
could engage in byte-flipping of subsequent fields if the wrong byte
order is detected here.
</para>
@ -478,7 +414,7 @@ order is detected here.
<term>Flags field</term>
<listitem>
<para>
int32 bit mask to denote important aspects of the file format. Bits are
32-bit integer bit mask to denote important aspects of the file format. Bits are
numbered from 0 (<acronym>LSB</>) to 31 (<acronym>MSB</>) --- note that this field is stored
with source's endianness, as are all subsequent integer fields. Bits
16-31 are reserved to denote critical file format issues; a reader
@ -491,7 +427,7 @@ only one flag bit is defined, and the rest must be zero:
<term>Bit 16</term>
<listitem>
<para>
if 1, OIDs are included in the dump; if 0, not
if 1, OIDs are included in the data; if 0, not
</para>
</listitem>
</varlistentry>
@ -504,8 +440,8 @@ only one flag bit is defined, and the rest must be zero:
<term>Header extension area length</term>
<listitem>
<para>
int32 length in bytes of remainder of header, not including self. In
the initial version this will be zero, and the first tuple follows
32-bit integer, length in bytes of remainder of header, not including self.
Currently, this is zero, and the first tuple follows
immediately. Future changes to the format might allow additional data
to be present in the header. A reader should silently skip over any header
extension data it does not know what to do with.
@ -531,17 +467,12 @@ is left for a later release.
</refsect3>
<refsect3>
<refsect3info>
<date>2001-01-02</date>
</refsect3info>
<title>
Tuples
</title>
<title>Tuples</title>
<para>
Each tuple begins with an int16 count of the number of fields in the
Each tuple begins with a 16-bit integer count of the number of fields in the
tuple. (Presently, all tuples in a table will have the same count, but
that might not always be true.) Then, repeated for each field in the
tuple, there is an int16 <structfield>typlen</> word possibly followed by field data.
tuple, there is a 16-bit integer <structfield>typlen</> word possibly followed by field data.
The <structfield>typlen</> field is interpreted thus:
<variablelist>
@ -549,7 +480,7 @@ The <structfield>typlen</> field is interpreted thus:
<term>Zero</term>
<listitem>
<para>
Field is NULL. No data follows.
Field is null. No data follows.
</para>
</listitem>
</varlistentry>
@ -558,7 +489,7 @@ The <structfield>typlen</> field is interpreted thus:
<term>&gt; 0</term>
<listitem>
<para>
Field is a fixed-length data type. Exactly N
Field is a fixed-length data type. Exactly that many
bytes of data follow the <structfield>typlen</> word.
</para>
</listitem>
@ -570,7 +501,7 @@ The <structfield>typlen</> field is interpreted thus:
<para>
Field is a <literal>varlena</> data type. The next four
bytes are the <literal>varlena</> header, which contains
the total value length including itself.
the total value length including the header itself.
</para>
</listitem>
</varlistentry>
@ -587,7 +518,7 @@ The <structfield>typlen</> field is interpreted thus:
</para>
<para>
For non-NULL fields, the reader can check that the <structfield>typlen</> matches the
For nonnull fields, the reader can check that the <structfield>typlen</> matches the
expected <structfield>typlen</> for the destination column. This provides a simple
but very useful check that the data is as expected.
</para>
@ -602,23 +533,19 @@ you from moving a binary file across machines).
</para>
<para>
If OIDs are included in the dump, the OID field immediately follows the
If OIDs are included in the file, the OID field immediately follows the
field-count word. It is a normal field except that it's not included
in the field-count. In particular it has a <structfield>typlen</> --- this will allow
handling of 4-byte vs 8-byte OIDs without too much pain, and will allow
OIDs to be shown as NULL if that ever proves desirable.
handling of 4-byte vs. 8-byte OIDs without too much pain, and will allow
OIDs to be shown as null if that ever proves desirable.
</para>
</refsect3>
<refsect3>
<refsect3info>
<date>2001-01-02</date>
</refsect3info>
<title>
File Trailer
</title>
<title>File Trailer</title>
<para>
The file trailer consists of an int16 word containing -1. This is
The file trailer consists of an 16-bit integer word containing -1. This is
easily distinguished from a tuple's field-count word.
</para>
@ -631,48 +558,47 @@ OIDs to be shown as NULL if that ever proves desirable.
</refsect2>
</refsect1>
<refsect1 id="R1-SQL-COPY-3">
<title>
Usage
</title>
<refsect1>
<title>Examples</title>
<para>
The following example copies a table to standard output,
using a vertical bar (|) as the field delimiter:
The following example copies a table to the client
using the vertical bar (<literal>|</literal>) as the field delimiter:
<programlisting>
COPY country TO STDOUT WITH DELIMITER '|';
</programlisting>
</para>
<programlisting>
COPY country TO <filename>stdout</filename> WITH DELIMITER '|';
</programlisting>
<para>
To copy data from a Unix file into the <literal>country</> table:
</para>
<programlisting>
To copy data from a file into the <literal>country</> table:
<programlisting>
COPY country FROM '/usr1/proj/bray/sql/country_data';
</programlisting>
</programlisting>
</para>
<para>
Here is a sample of data suitable for copying into a table from
<filename>stdin</filename> (so it has the termination sequence on the
<literal>STDIN</literal> (so it must have the termination sequence on the
last line):
</para>
<programlisting>
<programlisting>
AF AFGHANISTAN
AL ALBANIA
DZ ALGERIA
ZM ZAMBIA
ZW ZIMBABWE
\.
</programlisting>
<para>
Note that the white space on each line is actually a TAB.
</programlisting>
Note that the white space on each line is actually a tab character.
</para>
<para>
The following is the same data, output in binary format on a
Linux/i586 machine. The data is shown after filtering through the
Unix utility <command>od -c</command>. The table has three fields;
the first is <type>char(2)</type>, the second is <type>text</type>,
and the third is <type>integer</type>. All the rows have a null value
in the third field.
</para>
<programlisting>
Unix utility <command>od -c</command>. The table has three columns;
the first has type <type>char(2)</type>, the second has type <type>text</type>,
and the third has type <type>integer</type>. All the rows have a null value
in the third column.
<programlisting>
0000000 P G B C O P Y \n 377 \r \n \0 004 003 002 001
0000020 \0 \0 \0 \0 \0 \0 \0 \0 003 \0 377 377 006 \0 \0 \0
0000040 A F 377 377 017 \0 \0 \0 A F G H A N I S
@ -683,38 +609,33 @@ ZW ZIMBABWE
0000160 M 377 377 \n \0 \0 \0 Z A M B I A \0 \0 003
0000200 \0 377 377 006 \0 \0 \0 Z W 377 377 \f \0 \0 \0 Z
0000220 I M B A B W E \0 \0 377 377
</programlisting>
</programlisting>
</para>
</refsect1>
<refsect1 id="R1-SQL-COPY-6">
<title>
Compatibility
</title>
<refsect1>
<title>Compatibility</title>
<refsect2 id="R2-SQL-COPY-4">
<refsect2info>
<date>1998-09-08</date>
</refsect2info>
<title>
SQL92
</title>
<para>
There is no <command>COPY</command> statement in SQL92.
</para>
<para>
The following syntax was used by pre-7.3 applications and is still supported:
<synopsis>
COPY [ BINARY ] <replaceable class="parameter">table</replaceable> [ WITH OIDS ]
FROM { '<replaceable class="parameter">filename</replaceable>' | <filename>stdin</filename> }
[ [USING] DELIMITERS '<replaceable class="parameter">delimiter</replaceable>' ]
[ WITH NULL AS '<replaceable class="parameter">null string</replaceable>' ]
COPY [ BINARY ] <replaceable class="parameter">table</replaceable> [ WITH OIDS ]
TO { '<replaceable class="parameter">filename</replaceable>' | <filename>stdout</filename> }
[ [USING] DELIMITERS '<replaceable class="parameter">delimiter</replaceable>' ]
[ WITH NULL AS '<replaceable class="parameter">null string</replaceable>' ]
</synopsis>
</para>
</refsect2>
<para>
There is no <command>COPY</command> statement in the SQL standard.
</para>
<para>
The following syntax was used before PostgreSQL version 7.3 and is
still supported:
<synopsis>
COPY [ BINARY ] <replaceable class="parameter">table</replaceable> [ WITH OIDS ]
FROM { '<replaceable class="parameter">filename</replaceable>' | STDIN }
[ [USING] DELIMITERS '<replaceable class="parameter">delimiter</replaceable>' ]
[ WITH NULL AS '<replaceable class="parameter">null string</replaceable>' ]
COPY [ BINARY ] <replaceable class="parameter">table</replaceable> [ WITH OIDS ]
TO { '<replaceable class="parameter">filename</replaceable>' | STDOUT }
[ [USING] DELIMITERS '<replaceable class="parameter">delimiter</replaceable>' ]
[ WITH NULL AS '<replaceable class="parameter">null string</replaceable>' ]
</synopsis>
</para>
</refsect1>
</refentry>