Editorialization for the additions to the CREATE TABLE reference page

made as part of the recent INCLUDING CONSTRAINTS patch. The text could
stand further improvement, but this is at least a step in the right
direction.
This commit is contained in:
Neil Conway 2006-06-28 22:01:52 +00:00
parent 06bd3dba80
commit 6e9c974e43
1 changed files with 10 additions and 10 deletions

View File

@ -1,5 +1,5 @@
<!-- <!--
$PostgreSQL: pgsql/doc/src/sgml/ref/create_table.sgml,v 1.101 2006/06/27 03:43:19 momjian Exp $ $PostgreSQL: pgsql/doc/src/sgml/ref/create_table.sgml,v 1.102 2006/06/28 22:01:52 neilc Exp $
PostgreSQL documentation PostgreSQL documentation
--> -->
@ -249,19 +249,19 @@ and <replaceable class="PARAMETER">table_constraint</replaceable> is:
<para> <para>
Default expressions for the copied column definitions will only be Default expressions for the copied column definitions will only be
copied if <literal>INCLUDING DEFAULTS</literal> is specified. The copied if <literal>INCLUDING DEFAULTS</literal> is specified. The
default behavior is to exclude default expressions, resulting in default behavior is to exclude default expressions, resulting in the
all columns of the new table having null defaults. copied columns in the new table having null defaults.
</para> </para>
<para> <para>
Likewise constraints for the copied column definitions will only be Not-null constraints are always copied to the new table.
copied if <literal>INCLUDING CONSTRAINTS</literal> is specified. Note <literal>CHECK</literal> constraints will only be copied if
that currently even when <literal>INCLUDING CONSTRAINTS</literal> is specified <literal>INCLUDING CONSTRAINTS</literal> is specified; other types of
only CHECK constraints are copied. Also, no distinction is made between constraints will never be copied. Also, no distinction is made between
column constraints and table constraints -- when constraints are column constraints and table constraints &mdash; when constraints are
requested all check constraints are copied. requested, all check constraints are copied.
</para> </para>
<para> <para>
Note also that unlike <literal>INHERITS<literal> copied columns and Note also that unlike <literal>INHERITS</literal>, copied columns and
constraints are not merged with similarly named columns and constraints. constraints are not merged with similarly named columns and constraints.
If the same name is specified explicitly or in another If the same name is specified explicitly or in another
<literal>LIKE</literal> clause an error is signalled. <literal>LIKE</literal> clause an error is signalled.