Add backup/restore info to Admin Guide.
Split management chapter from start-ag.sgml to manage-ag.sgml.
This commit is contained in:
Thomas G. Lockhart
parent
66ef1b6ebd
commit
b32ffb7345
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@ -1,11 +1,15 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/admin.sgml,v 1.15 1999/06/03 04:21:47 thomas Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/admin.sgml,v 1.16 1999/06/23 06:15:13 thomas Exp $
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Postgres Administrator's Guide.
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Derived from postgres.sgml.
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- thomas 1998-10-27
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$Log: admin.sgml,v $
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Revision 1.16 1999/06/23 06:15:13 thomas
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Add backup/restore info to Admin Guide.
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Split management chapter from start-ag.sgml to manage-ag.sgml.
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Revision 1.15 1999/06/03 04:21:47 thomas
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Markup changes for v6.5 release.
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Clean out duplicate stuff in odbc.sgml resulting from a faulty patch.
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@ -54,28 +58,29 @@ Bigger updates to the installation instructions (install and config).
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<!doctype book PUBLIC "-//Davenport//DTD DocBook V3.0//EN" [
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<!entity about SYSTEM "about.sgml">
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||||
<!entity history SYSTEM "history.sgml">
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||||
<!entity info SYSTEM "info.sgml">
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||||
<!entity legal SYSTEM "legal.sgml">
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||||
<!entity notation SYSTEM "notation.sgml">
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<!entity y2k SYSTEM "y2k.sgml">
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||||
<!entity about SYSTEM "about.sgml">
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||||
<!entity history SYSTEM "history.sgml">
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||||
<!entity info SYSTEM "info.sgml">
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||||
<!entity legal SYSTEM "legal.sgml">
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||||
<!entity notation SYSTEM "notation.sgml">
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||||
<!entity y2k SYSTEM "y2k.sgml">
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||||
|
||||
<!entity config SYSTEM "config.sgml">
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||||
<!entity intro-ag SYSTEM "intro-ag.sgml">
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||||
<!entity install SYSTEM "install.sgml">
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||||
<!entity installw SYSTEM "install-win32.sgml">
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||||
<!entity layout SYSTEM "layout.sgml">
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||||
<!entity ports SYSTEM "ports.sgml">
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<!entity recovery SYSTEM "recovery.sgml">
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<!entity regress SYSTEM "regress.sgml">
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||||
<!entity release SYSTEM "release.sgml">
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||||
<!entity runtime SYSTEM "runtime.sgml">
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<!entity security SYSTEM "security.sgml">
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<!entity start-ag SYSTEM "start-ag.sgml">
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<!entity trouble SYSTEM "trouble.sgml">
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||||
<!entity config SYSTEM "config.sgml">
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<!entity intro-ag SYSTEM "intro-ag.sgml">
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<!entity install SYSTEM "install.sgml">
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<!entity installw SYSTEM "install-win32.sgml">
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||||
<!entity layout SYSTEM "layout.sgml">
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<!entity manage-ag SYSTEM "manage-ag.sgml">
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<!entity ports SYSTEM "ports.sgml">
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<!entity recovery SYSTEM "recovery.sgml">
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<!entity regress SYSTEM "regress.sgml">
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<!entity release SYSTEM "release.sgml">
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<!entity runtime SYSTEM "runtime.sgml">
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<!entity security SYSTEM "security.sgml">
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<!entity start-ag SYSTEM "start-ag.sgml">
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<!entity trouble SYSTEM "trouble.sgml">
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<!entity biblio SYSTEM "biblio.sgml">
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<!entity biblio SYSTEM "biblio.sgml">
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]>
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<Book Id="admin">
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@ -157,6 +162,7 @@ Your name here...
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&runtime;
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&security;
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&start-ag;
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&manage-ag;
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&trouble;
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&recovery;
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®ress;
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|
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@ -0,0 +1,297 @@
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<chapter id="manage-ag">
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<title>Managing a Database</title>
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<para>
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If the <productname>Postgres</productname>
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<application>postmaster</application> is up and running we can create
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some databases to experiment with. Here, we describe the
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basic commands for managing a database.
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</para>
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<sect1>
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<title>Creating a Database</title>
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<para>
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Let's say you want to create a database named mydb.
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You can do this with the following command:
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<programlisting>
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% createdb <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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<productname>Postgres</productname> allows you to create
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any number of databases
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at a given site and you automatically become the
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database administrator of the database you just created.
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Database names must have an alphabetic first
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character and are limited to 16 characters in length.
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Not every user has authorization to become a database
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administrator. If <productname>Postgres</productname>
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refuses to create databases
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for you, then the site administrator needs to grant you
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permission to create databases. Consult your site
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administrator if this occurs.
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</para>
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</sect1>
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<sect1>
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<title>Accessing a Database</title>
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<para>
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Once you have constructed a database, you can access it
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by:
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<itemizedlist spacing="compact" mark="bullet">
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<listitem>
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<para>
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running the <productname>Postgres</productname> terminal monitor program
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(<application>psql</application>) which allows you to interactively
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enter, edit, and execute <acronym>SQL</acronym> commands.
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</para>
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</listitem>
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<listitem>
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<para>
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writing a C program using the <literal>libpq</literal> subroutine
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library. This allows you to submit <acronym>SQL</acronym> commands
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from C and get answers and status messages back to
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your program. This interface is discussed further
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in the <citetitle>PostgreSQL Programmer's Guide</citetitle>.
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</para>
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</listitem>
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</itemizedlist>
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You might want to start up <application>psql</application>,
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to try out the examples in this manual. It can be activated for the
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<replaceable class="parameter">dbname</replaceable> database by typing the command:
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<programlisting>
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% psql <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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You will be greeted with the following message:
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<programlisting>
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Welcome to the Postgres interactive sql monitor:
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type \? for help on slash commands
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type \q to quit
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type \g or terminate with semicolon to execute query
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You are currently connected to the database: <replaceable>dbname</replaceable>
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<replaceable>dbname</replaceable>=>
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</programlisting>
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</para>
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<para>
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This prompt indicates that the terminal monitor is listening
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to you and that you can type <acronym>SQL</acronym> queries into a
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workspace maintained by the terminal monitor.
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The <application>psql</application> program responds to escape
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codes that begin
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with the backslash character, "\". For example, you
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can get help on the syntax of various
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<productname>Postgres</productname> <acronym>SQL</acronym> commands by typing:
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<programlisting>
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<replaceable>dbname</replaceable>=> \h
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</programlisting>
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Once you have finished entering your queries into the
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workspace, you can pass the contents of the workspace
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to the <productname>Postgres</productname> server by typing:
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<programlisting>
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<replaceable>dbname</replaceable>=> \g
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</programlisting>
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This tells the server to process the query. If you
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terminate your query with a semicolon, the backslash-g is not
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necessary. <application>psql</application> will automatically
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process semicolon terminated queries.
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To read queries from a file, instead of
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entering them interactively, type:
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<programlisting>
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<replaceable>dbname</replaceable>=> \i <replaceable class="parameter">filename</replaceable>
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</programlisting>
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To get out of <application>psql</application> and return to UNIX, type
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<programlisting>
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<replaceable>dbname</replaceable>=> \q
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</programlisting>
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and <application>psql</application> will quit and return
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you to your command shell. (For more escape codes, type
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backslash-h at the monitor prompt.)
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White space (i.e., spaces, tabs and newlines) may be
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used freely in <acronym>SQL</acronym> queries.
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Single-line comments are denoted by two dashes
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(<quote>--</quote>). Everything after the dashes up to the end of the
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line is ignored. Multiple-line comments, and comments within a line,
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are denoted by <quote>/* ... */</quote>, a convention borrowed
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from <productname>Ingres</productname>.
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</para>
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</sect1>
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<sect1>
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<title>Destroying a Database</title>
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<para>
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If you are the database administrator for the database
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mydb, you can destroy it using the following UNIX command:
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<programlisting>
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% destroydb <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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This action physically removes all of the UNIX files
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associated with the database and cannot be undone, so
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this should only be done with a great deal of forethought.
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</para>
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<para>
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It is also possible to destroy a database from within an
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<acronym>SQL</acronym> session by using
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<programlisting>
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> drop database <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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</para>
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</sect1>
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<sect1>
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<title>Backup and Restore</title>
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<caution>
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<para>
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Every database should be backed up on a regular basis. Since
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<productname>Postgres</productname> manages it's own files in the
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file system, it is <emphasis>not advisable</emphasis> to rely on
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system backups of your file system for your database backups;
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there is no guarantee that the files will be in a usable,
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consistant state after restoration.
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</para>
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</caution>
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<para>
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<productname>Postgres</productname> provides two utilities to
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backup your system: <application>pg_dump</application> to backup
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individual databases and
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<application>pg_dumpall</application> to backup your installation
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in one step.
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</para>
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<para>
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An individual database can be backed up using the following
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command:
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<programlisting>
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% pg_dump <replaceable class="parameter">dbname</replaceable> > <replaceable class="parameter">dbname</replaceable>.pgdump
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</programlisting>
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and can be restored using
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<programlisting>
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cat <replaceable class="parameter">dbname</replaceable>.pgdump | psql <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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</para>
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<para>
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This technique can be used to move databases to new
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locations, and to rename existing databases.
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</para>
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<sect2>
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<title>Large Databases</title>
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<note>
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<title>Author</title>
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<para>
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Written by <ulink url="hannu@trust.ee">Hannu Krosing</ulink> on
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1999-06-19.
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</para>
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</note>
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<para>
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Since <productname>Postgres</productname> allows tables larger
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than the maximum file size on your system, it can be problematic
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to dump the table to a file, since the resulting file will likely
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be larger than the maximum size allowed by your system.</para>
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<para>
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As <application>pg_dump</application> writes to stdout,
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you can just use standard *nix tools
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to work around this possible problem:
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<itemizedlist>
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<listitem>
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<para>
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Use compressed dumps:
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<programlisting>
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% pg_dump <replaceable class="parameter">dbname</replaceable> | gzip > <replaceable class="parameter">filename</replaceable>.dump.gz
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</programlisting>
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reload with
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<programlisting>
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% createdb <replaceable class="parameter">dbname</replaceable>
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% gunzip -c <replaceable class="parameter">filename</replaceable>.dump.gz | psql <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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or
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<programlisting>
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% cat <replaceable class="parameter">filename</replaceable>.dump.gz | gunzip | psql <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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</para>
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</listitem>
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<listitem>
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<para>
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Use split:
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<programlisting>
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% pg_dump <replaceable class="parameter">dbname</replaceable> | split -b 1m - <replaceable class="parameter">filename</replaceable>.dump.
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</programlisting>
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reload with
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<programlisting>
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% createdb <replaceable class="parameter">dbname</replaceable>
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% cat <replaceable class="parameter">filename</replaceable>.dump.* | pgsql <replaceable class="parameter">dbname</replaceable>
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</programlisting>
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</para>
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</listitem>
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</itemizedlist>
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</para>
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<para>
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Of course, the name of the file
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(<replaceable class="parameter">filename</replaceable>) and the
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content of the <application>pg_dump</application> output need not
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match the name of the database. Also, the restored database can
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have an arbitrary new name, so this mechanism is also suitable
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for renaming databases.
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</sect2>
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</sect1>
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</chapter>
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<!-- Keep this comment at the end of the file
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Local variables:
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mode: sgml
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sgml-omittag:nil
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sgml-shorttag:t
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sgml-minimize-attributes:nil
|
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sgml-always-quote-attributes:t
|
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sgml-indent-step:1
|
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sgml-indent-data:t
|
||||
sgml-parent-document:nil
|
||||
sgml-default-dtd-file:"./reference.ced"
|
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sgml-exposed-tags:nil
|
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sgml-local-catalogs:"/usr/lib/sgml/CATALOG"
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sgml-local-ecat-files:nil
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End:
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-->
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@ -1,11 +1,15 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/postgres.sgml,v 1.27 1999/06/03 04:21:49 thomas Exp $
|
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$Header: /cvsroot/pgsql/doc/src/sgml/postgres.sgml,v 1.28 1999/06/23 06:15:12 thomas Exp $
|
||||
|
||||
Postgres integrated documentation.
|
||||
Other subset docs should be copied and shrunk from here.
|
||||
thomas 1998-02-23
|
||||
|
||||
$Log: postgres.sgml,v $
|
||||
Revision 1.28 1999/06/23 06:15:12 thomas
|
||||
Add backup/restore info to Admin Guide.
|
||||
Split management chapter from start-ag.sgml to manage-ag.sgml.
|
||||
|
||||
Revision 1.27 1999/06/03 04:21:49 thomas
|
||||
Markup changes for v6.5 release.
|
||||
Clean out duplicate stuff in odbc.sgml resulting from a faulty patch.
|
||||
|
|
@ -136,19 +140,20 @@ Move SQL reference pages up into the User's Guide.
|
|||
%allfiles;
|
||||
|
||||
<!-- administrator's guide -->
|
||||
<!entity config SYSTEM "config.sgml">
|
||||
<!entity install SYSTEM "install.sgml">
|
||||
<!entity installw SYSTEM "install-win32.sgml">
|
||||
<!entity intro-ag SYSTEM "intro-ag.sgml">
|
||||
<!entity layout SYSTEM "layout.sgml">
|
||||
<!entity ports SYSTEM "ports.sgml">
|
||||
<!entity runtime SYSTEM "runtime.sgml">
|
||||
<!entity recovery SYSTEM "recovery.sgml">
|
||||
<!entity regress SYSTEM "regress.sgml">
|
||||
<!entity release SYSTEM "release.sgml">
|
||||
<!entity security SYSTEM "security.sgml">
|
||||
<!entity start-ag SYSTEM "start-ag.sgml">
|
||||
<!entity trouble SYSTEM "trouble.sgml">
|
||||
<!entity config SYSTEM "config.sgml">
|
||||
<!entity intro-ag SYSTEM "intro-ag.sgml">
|
||||
<!entity install SYSTEM "install.sgml">
|
||||
<!entity installw SYSTEM "install-win32.sgml">
|
||||
<!entity layout SYSTEM "layout.sgml">
|
||||
<!entity manage-ag SYSTEM "manage-ag.sgml">
|
||||
<!entity ports SYSTEM "ports.sgml">
|
||||
<!entity recovery SYSTEM "recovery.sgml">
|
||||
<!entity regress SYSTEM "regress.sgml">
|
||||
<!entity release SYSTEM "release.sgml">
|
||||
<!entity runtime SYSTEM "runtime.sgml">
|
||||
<!entity security SYSTEM "security.sgml">
|
||||
<!entity start-ag SYSTEM "start-ag.sgml">
|
||||
<!entity trouble SYSTEM "trouble.sgml">
|
||||
|
||||
<!-- programmer's guide -->
|
||||
<!entity intro-pg SYSTEM "intro-pg.sgml">
|
||||
|
|
@ -266,6 +271,7 @@ Your name here...
|
|||
</Para>
|
||||
</PartIntro>
|
||||
|
||||
&intro;
|
||||
&syntax;
|
||||
&datatype;
|
||||
&oper;
|
||||
|
|
@ -302,6 +308,7 @@ Your name here...
|
|||
&runtime;
|
||||
&security;
|
||||
&start-ag;
|
||||
&manage-ag;
|
||||
&trouble;
|
||||
&recovery;
|
||||
®ress;
|
||||
|
|
@ -379,7 +386,6 @@ Your name here...
|
|||
Introduction for new users.
|
||||
</Para>
|
||||
</PartIntro>
|
||||
&intro;
|
||||
&sql;
|
||||
&arch;
|
||||
&start;
|
||||
|
|
|
|||
|
|
@ -4,37 +4,38 @@
|
|||
- - thomas 1998-02-24
|
||||
-->
|
||||
|
||||
<Chapter Id="newuser">
|
||||
<Title>Adding and Deleting Users</Title>
|
||||
<chapter id="newuser">
|
||||
<title>Adding and Deleting Users</title>
|
||||
|
||||
<Para>
|
||||
<Application>createuser</Application> enables specific users to access
|
||||
<ProductName>Postgres</ProductName>.
|
||||
<Application>destroyuser</Application> removes users and
|
||||
prevents them from accessing <ProductName>Postgres</ProductName>.
|
||||
Note that these
|
||||
commands only affect users with respect to
|
||||
<ProductName>Postgres</ProductName>;
|
||||
they have no effect on users other privileges or status with regards
|
||||
to the underlying
|
||||
operating system.
|
||||
</Para>
|
||||
</Chapter>
|
||||
<para>
|
||||
<application>createuser</application> enables specific users to access
|
||||
<productname>Postgres</productname>.
|
||||
<application>destroyuser</application> removes users and
|
||||
prevents them from accessing <productname>Postgres</productname>.
|
||||
</para>
|
||||
|
||||
<Chapter Id="disk">
|
||||
<Title>Disk Management</Title>
|
||||
<para>
|
||||
These commands only affect users with respect to
|
||||
<productname>Postgres</productname>;
|
||||
they have no effect on a user's other privileges or status with regards
|
||||
to the underlying operating system.
|
||||
</para>
|
||||
</chapter>
|
||||
|
||||
<Sect1>
|
||||
<Title>Alternate Locations</Title>
|
||||
<chapter id="disk">
|
||||
<title>Disk Management</title>
|
||||
|
||||
<Para>
|
||||
<sect1>
|
||||
<title>Alternate Locations</title>
|
||||
|
||||
<para>
|
||||
It is possible to create a database in a location other than the default
|
||||
location for the installation. Remember that all database access actually
|
||||
occurs through the database backend, so that any location specified must
|
||||
be accessible by the backend.
|
||||
</para>
|
||||
|
||||
<Para>
|
||||
<para>
|
||||
Alternate database locations are created and referenced by an environment variable
|
||||
which gives the absolute path to the intended storage location.
|
||||
This environment variable must have been defined before the backend was started
|
||||
|
|
@ -44,45 +45,45 @@
|
|||
to avoid confusion and conflict with other variables.
|
||||
</para>
|
||||
|
||||
<Note>
|
||||
<Para>
|
||||
In previous versions of <ProductName>Postgres</ProductName>,
|
||||
<note>
|
||||
<para>
|
||||
In previous versions of <productname>Postgres</productname>,
|
||||
it was also permissable to use an absolute path name
|
||||
to specify an alternate storage location.
|
||||
The environment variable style of specification
|
||||
is to be preferred since it allows the site administrator more flexibility in
|
||||
managing disk storage.
|
||||
If you prefer using absolute paths, you may do so by defining
|
||||
"ALLOW_ABSOLUTE_DBPATHS" and recompiling <ProductName>Postgres</ProductName>
|
||||
"ALLOW_ABSOLUTE_DBPATHS" and recompiling <productname>Postgres</productname>
|
||||
To do this, either add this line
|
||||
|
||||
<ProgramListing>
|
||||
<programlisting>
|
||||
#define ALLOW_ABSOLUTE_DBPATHS 1
|
||||
</ProgramListing>
|
||||
</programlisting>
|
||||
|
||||
to the file <filename>src/include/config.h</filename>, or by specifying
|
||||
|
||||
<ProgramListing>
|
||||
<programlisting>
|
||||
CFLAGS+= -DALLOW_ABSOLUTE_DBPATHS
|
||||
</ProgramListing>
|
||||
</programlisting>
|
||||
|
||||
in your <filename>Makefile.custom</filename>.
|
||||
</Para>
|
||||
</Note>
|
||||
</para>
|
||||
</note>
|
||||
|
||||
<Para>
|
||||
<para>
|
||||
Remember that database creation is actually performed by the database backend.
|
||||
Therefore, any environment variable specifying an alternate location must have
|
||||
been defined before the backend was started. To define an alternate location
|
||||
PGDATA2 pointing to <filename>/home/postgres/data</filename>, first type
|
||||
|
||||
<ProgramListing>
|
||||
<programlisting>
|
||||
% setenv PGDATA2 /home/postgres/data
|
||||
</ProgramListing>
|
||||
</programlisting>
|
||||
|
||||
to define the environment variable to be used with subsequent commands.
|
||||
Usually, you will want to define this variable in the
|
||||
<ProductName>Postgres</ProductName> superuser's
|
||||
<productname>Postgres</productname> superuser's
|
||||
<filename>.profile</filename>
|
||||
or
|
||||
<filename>.cshrc</filename>
|
||||
|
|
@ -93,187 +94,33 @@
|
|||
overwriting other variables.
|
||||
</para>
|
||||
|
||||
<Para>
|
||||
<para>
|
||||
To create a data storage area in PGDATA2, ensure
|
||||
that <filename>/home/postgres</filename> already exists and is writable
|
||||
by the postgres administrator.
|
||||
Then from the command line, type
|
||||
|
||||
<ProgramListing>
|
||||
<programlisting>
|
||||
% setenv PGDATA2 /home/postgres/data
|
||||
% initlocation $PGDATA2
|
||||
Creating Postgres database system directory /home/postgres/data
|
||||
|
||||
Creating Postgres database system directory /home/postgres/data/base
|
||||
|
||||
</ProgramListing>
|
||||
</programlisting>
|
||||
|
||||
</para>
|
||||
<Para>
|
||||
To test the new location, create a database <Database>test</Database> by typing
|
||||
<para>
|
||||
To test the new location, create a database <database>test</database> by typing
|
||||
|
||||
<ProgramListing>
|
||||
<programlisting>
|
||||
% createdb -D PGDATA2 test
|
||||
% destroydb test
|
||||
</ProgramListing>
|
||||
</programlisting>
|
||||
|
||||
</para>
|
||||
</Sect1>
|
||||
</Chapter>
|
||||
|
||||
<Chapter Id="manage-ag">
|
||||
<Title>Managing a Database</Title>
|
||||
|
||||
<Para>
|
||||
Now that <ProductName>Postgres</ProductName> is up and running we can create
|
||||
some databases to experiment with. Here, we describe the
|
||||
basic commands for managing a database.
|
||||
</Para>
|
||||
|
||||
<Sect1>
|
||||
<Title>Creating a Database</Title>
|
||||
|
||||
<Para>
|
||||
Let's say you want to create a database named mydb.
|
||||
You can do this with the following command:
|
||||
|
||||
<ProgramListing>
|
||||
% createdb mydb
|
||||
</ProgramListing>
|
||||
|
||||
<ProductName>Postgres</ProductName> allows you to create
|
||||
any number of databases
|
||||
at a given site and you automatically become the
|
||||
database administrator of the database you just created.
|
||||
Database names must have an alphabetic first
|
||||
character and are limited to 16 characters in length.
|
||||
Not every user has authorization to become a database
|
||||
administrator. If <ProductName>Postgres</ProductName>
|
||||
refuses to create databases
|
||||
for you, then the site administrator needs to grant you
|
||||
permission to create databases. Consult your site
|
||||
administrator if this occurs.
|
||||
</Para>
|
||||
</Sect1>
|
||||
|
||||
<Sect1>
|
||||
<Title>Accessing a Database</Title>
|
||||
|
||||
<Para>
|
||||
Once you have constructed a database, you can access it
|
||||
by:
|
||||
|
||||
<ItemizedList Mark="bullet" Spacing="compact">
|
||||
<ListItem>
|
||||
<Para>
|
||||
running the <ProductName>Postgres</ProductName> terminal monitor program
|
||||
(<Application>psql</Application>) which allows you to interactively
|
||||
enter, edit, and execute <Acronym>SQL</Acronym> commands.
|
||||
</Para>
|
||||
</ListItem>
|
||||
<ListItem>
|
||||
<Para>
|
||||
writing a C program using the <literal>libpq</literal> subroutine
|
||||
library. This allows you to submit <Acronym>SQL</Acronym> commands
|
||||
from C and get answers and status messages back to
|
||||
your program. This interface is discussed further
|
||||
in the <citetitle>PostgreSQL Programmer's Guide</citetitle>.
|
||||
</Para>
|
||||
</ListItem>
|
||||
</ItemizedList>
|
||||
|
||||
You might want to start up <Application>psql</Application>,
|
||||
to try out the examples in this manual. It can be activated for the mydb
|
||||
database by typing the command:
|
||||
|
||||
<ProgramListing>
|
||||
% psql mydb
|
||||
</ProgramListing>
|
||||
|
||||
You will be greeted with the following message:
|
||||
<ProgramListing>
|
||||
Welcome to the Postgres interactive sql monitor:
|
||||
|
||||
type \? for help on slash commands
|
||||
type \q to quit
|
||||
type \g or terminate with semicolon to execute query
|
||||
You are currently connected to the database: mydb
|
||||
|
||||
mydb=>
|
||||
</ProgramListing>
|
||||
</Para>
|
||||
|
||||
<Para>
|
||||
This prompt indicates that the terminal monitor is listening
|
||||
to you and that you can type <Acronym>SQL</Acronym> queries into a
|
||||
workspace maintained by the terminal monitor.
|
||||
The <Application>psql</Application> program responds to escape
|
||||
codes that begin
|
||||
with the backslash character, "\". For example, you
|
||||
can get help on the syntax of various
|
||||
<ProductName>Postgres</ProductName> <Acronym>SQL</Acronym> commands by typing:
|
||||
|
||||
<ProgramListing>
|
||||
mydb=> \h
|
||||
</ProgramListing>
|
||||
|
||||
Once you have finished entering your queries into the
|
||||
workspace, you can pass the contents of the workspace
|
||||
to the <ProductName>Postgres</ProductName> server by typing:
|
||||
|
||||
<ProgramListing>
|
||||
mydb=> \g
|
||||
</ProgramListing>
|
||||
|
||||
This tells the server to process the query. If you
|
||||
terminate your query with a semicolon, the backslash-g is not
|
||||
necessary. <Application>psql</Application> will automatically
|
||||
process semicolon terminated queries.
|
||||
To read queries from a file, say myFile, instead of
|
||||
entering them interactively, type:
|
||||
|
||||
<ProgramListing>
|
||||
mydb=> \i fileName
|
||||
</ProgramListing>
|
||||
|
||||
To get out of <Application>psql</Application> and return to UNIX, type
|
||||
|
||||
<ProgramListing>
|
||||
mydb=> \q
|
||||
</ProgramListing>
|
||||
|
||||
and <Application>psql</Application> will quit and return
|
||||
you to your command
|
||||
shell. (For more escape codes, type backslash-h at the monitor
|
||||
prompt.)
|
||||
White space (i.e., spaces, tabs and newlines) may be
|
||||
used freely in <Acronym>SQL</Acronym> queries.
|
||||
Single-line comments are denoted by two dashes
|
||||
(<Quote>--</Quote>). Everything after the dashes up to the end of the
|
||||
line is ignored. Multiple-line comments, and comments within a line,
|
||||
are denoted by <Quote>/* ... */</Quote>, a convention borrowed
|
||||
from <productname>Ingres</productname>.
|
||||
</Para>
|
||||
</Sect1>
|
||||
|
||||
<Sect1>
|
||||
<Title>Destroying a Database</Title>
|
||||
|
||||
<Para>
|
||||
If you are the database administrator for the database
|
||||
mydb, you can destroy it using the following UNIX command:
|
||||
|
||||
<ProgramListing>
|
||||
% destroydb mydb
|
||||
</ProgramListing>
|
||||
|
||||
This action physically removes all of the UNIX files
|
||||
associated with the database and cannot be undone, so
|
||||
this should only be done with a great deal of forethought.
|
||||
</Para>
|
||||
</Sect1>
|
||||
|
||||
</Chapter>
|
||||
</sect1>
|
||||
</chapter>
|
||||
|
||||
<!-- Keep this comment at the end of the file
|
||||
Local variables:
|
||||
|
|
|
|||
Loading…
Reference in New Issue