diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/ref/alter_index.sgml | 3 | ||||
| -rw-r--r-- | doc/src/sgml/ref/alter_table.sgml | 37 | ||||
| -rw-r--r-- | doc/src/sgml/ref/create_table.sgml | 24 |
3 files changed, 48 insertions, 16 deletions
diff --git a/doc/src/sgml/ref/alter_index.sgml b/doc/src/sgml/ref/alter_index.sgml index 7290d9a5bda..d0a62123583 100644 --- a/doc/src/sgml/ref/alter_index.sgml +++ b/doc/src/sgml/ref/alter_index.sgml @@ -48,6 +48,9 @@ ALTER INDEX ALL IN TABLESPACE <replaceable class="parameter">name</replaceable> <listitem> <para> The <literal>RENAME</literal> form changes the name of the index. + If the index is associated with a table constraint (either + <literal>UNIQUE</literal>, <literal>PRIMARY KEY</literal>, + or <literal>EXCLUDE</literal>), the constraint is renamed as well. There is no effect on the stored data. </para> </listitem> diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml index 1cce00eaf92..ec6b4c33113 100644 --- a/doc/src/sgml/ref/alter_table.sgml +++ b/doc/src/sgml/ref/alter_table.sgml @@ -474,7 +474,8 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM <term><literal>DROP CONSTRAINT [ IF EXISTS ]</literal></term> <listitem> <para> - This form drops the specified constraint on a table. + This form drops the specified constraint on a table, along with + any index underlying the constraint. If <literal>IF EXISTS</literal> is specified and the constraint does not exist, no error is thrown. In this case a notice is issued instead. </para> @@ -822,8 +823,10 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM <listitem> <para> The <literal>RENAME</literal> forms change the name of a table - (or an index, sequence, view, materialized view, or foreign table), the name - of an individual column in a table, or the name of a constraint of the table. + (or an index, sequence, view, materialized view, or foreign table), the + name of an individual column in a table, or the name of a constraint of + the table. When renaming a constraint that has an underlying index, + the index is renamed as well. There is no effect on the stored data. </para> </listitem> @@ -1270,10 +1273,12 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM <para> If a table has any descendant tables, it is not permitted to add, rename, or change the type of a column in the parent table without doing - same to the descendants. This ensures that the descendants always have - columns matching the parent. Similarly, a constraint cannot be renamed - in the parent without also renaming it in all descendants, so that - constraints also match between the parent and its descendants. + the same to the descendants. This ensures that the descendants always + have columns matching the parent. Similarly, a <literal>CHECK</literal> + constraint cannot be renamed in the parent without also renaming it in + all descendants, so that <literal>CHECK</literal> constraints also match + between the parent and its descendants. (That restriction does not apply + to index-based constraints, however.) Also, because selecting from the parent also selects from its descendants, a constraint on the parent cannot be marked valid unless it is also marked valid for those descendants. In all of these cases, <command>ALTER TABLE @@ -1481,35 +1486,35 @@ ALTER TABLE distributors DROP CONSTRAINT distributors_pkey, </programlisting></para> <para> - Attach a partition to range partitioned table: + To attach a partition to a range-partitioned table: <programlisting> ALTER TABLE measurement ATTACH PARTITION measurement_y2016m07 FOR VALUES FROM ('2016-07-01') TO ('2016-08-01'); </programlisting></para> <para> - Attach a partition to list partitioned table: + To attach a partition to a list-partitioned table: <programlisting> ALTER TABLE cities ATTACH PARTITION cities_ab FOR VALUES IN ('a', 'b'); </programlisting></para> <para> - Attach a default partition to a partitioned table: + To attach a partition to a hash-partitioned table: <programlisting> -ALTER TABLE cities - ATTACH PARTITION cities_partdef DEFAULT; +ALTER TABLE orders + ATTACH PARTITION orders_p4 FOR VALUES WITH (MODULUS 4, REMAINDER 3); </programlisting></para> <para> - Attach a partition to hash partitioned table: + To attach a default partition to a partitioned table: <programlisting> -ALTER TABLE orders - ATTACH PARTITION orders_p4 FOR VALUES WITH (MODULUS 4, REMAINDER 3); +ALTER TABLE cities + ATTACH PARTITION cities_partdef DEFAULT; </programlisting></para> <para> - Detach a partition from partitioned table: + To detach a partition from a partitioned table: <programlisting> ALTER TABLE measurement DETACH PARTITION measurement_y2015m12; diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml index d936de3f238..5a19f94ce91 100644 --- a/doc/src/sgml/ref/create_table.sgml +++ b/doc/src/sgml/ref/create_table.sgml @@ -2005,6 +2005,30 @@ CREATE TABLE cities_partdef </refsect2> <refsect2> + <title>Constraint Naming</title> + + <para> + The SQL standard says that table and domain constraints must have names + that are unique across the schema containing the table or domain. + <productname>PostgreSQL</productname> is laxer: it only requires + constraint names to be unique across the constraints attached to a + particular table or domain. However, this extra freedom does not exist + for index-based constraints (<literal>UNIQUE</literal>, + <literal>PRIMARY KEY</literal>, and <literal>EXCLUDE</literal> + constraints), because the associated index is named the same as the + constraint, and index names must be unique across all relations within + the same schema. + </para> + + <para> + Currently, <productname>PostgreSQL</productname> does not record names + for <literal>NOT NULL</literal> constraints at all, so they are not + subject to the uniqueness restriction. This might change in a future + release. + </para> + </refsect2> + + <refsect2> <title>Inheritance</title> <para> |