diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml index 7326bbe01c1ebe491325ced124384df89aa2f64e..eea25682eb095146606786eade15590aeb9f6797 100644 --- a/doc/src/sgml/ref/alter_table.sgml +++ b/doc/src/sgml/ref/alter_table.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.50 2002/09/21 18:32:54 petere Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/alter_table.sgml,v 1.51 2002/10/19 22:51:45 tgl Exp $ PostgreSQL documentation --> @@ -38,9 +38,9 @@ ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ] class="PARAMETER">new_column</replaceable> ALTER TABLE <replaceable class="PARAMETER">table</replaceable> RENAME TO <replaceable class="PARAMETER">new_table</replaceable> -ALTER TABLE <replaceable class="PARAMETER">table</replaceable> - ADD <replaceable class="PARAMETER">table_constraint_definition</replaceable> -ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> +ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ] + ADD <replaceable class="PARAMETER">table_constraint</replaceable> +ALTER TABLE [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ * ] DROP CONSTRAINT <replaceable class="PARAMETER">constraint_name</replaceable> [ RESTRICT | CASCADE ] ALTER TABLE <replaceable class="PARAMETER">table</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable> @@ -110,7 +110,7 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable> </varlistentry> <varlistentry> - <term><replaceable class="PARAMETER"> table_constraint_definition </replaceable></term> + <term><replaceable class="PARAMETER"> table_constraint </replaceable></term> <listitem> <para> New table constraint for the table. @@ -298,7 +298,7 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable> </varlistentry> <varlistentry> - <term>ADD <replaceable class="PARAMETER">table_constraint_definition</replaceable></term> + <term>ADD <replaceable class="PARAMETER">table_constraint</replaceable></term> <listitem> <para> This form adds a new constraint to a table using the same syntax as @@ -311,7 +311,7 @@ ALTER TABLE <replaceable class="PARAMETER">table</replaceable> <term>DROP CONSTRAINT</term> <listitem> <para> - This form drops constraints on a table (and its children). + This form drops constraints on a table. Currently, constraints on tables are not required to have unique names, so there may be more than one constraint matching the specified name. All such constraints will be dropped. @@ -376,6 +376,22 @@ VACUUM FULL table; </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, ALTER TABLE ONLY will be rejected. This + ensures that the descendants always have columns matching the parent. + </para> + + <para> + A recursive DROP COLUMN operation will remove a descendant table's column + only if the descendant does not inherit that column from any other + parents and never had an independent definition of the column. + A nonrecursive DROP COLUMN (i.e., ALTER TABLE ONLY ... DROP COLUMN) + never removes any descendant columns, but instead marks them as + independently defined rather than inherited. + </para> + <para> Changing any part of the schema of a system catalog is not permitted.