diff options
Diffstat (limited to 'doc/src/sgml/ref/alter_table.sgml')
| -rw-r--r-- | doc/src/sgml/ref/alter_table.sgml | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml index ece438f0075..a75e75d800d 100644 --- a/doc/src/sgml/ref/alter_table.sgml +++ b/doc/src/sgml/ref/alter_table.sgml @@ -243,6 +243,8 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM entire table; however, if a valid <literal>CHECK</literal> constraint is found which proves no <literal>NULL</literal> can exist, then the table scan is skipped. + If a column has an invalid not-null constraint, + <literal>SET NOT NULL</literal> validates it. </para> <para> @@ -458,8 +460,8 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM <para> This form adds a new constraint to a table using the same constraint syntax as <link linkend="sql-createtable"><command>CREATE TABLE</command></link>, plus the option <literal>NOT - VALID</literal>, which is currently only allowed for foreign key - and CHECK constraints. + VALID</literal>, which is currently only allowed for foreign key, + <literal>CHECK</literal> constraints and not-null constraints. </para> <para> @@ -586,7 +588,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM <term><literal>VALIDATE CONSTRAINT</literal></term> <listitem> <para> - This form validates a foreign key or check constraint that was + This form validates a foreign key, check, or not-null constraint that was previously created as <literal>NOT VALID</literal>, by scanning the table to ensure there are no rows for which the constraint is not satisfied. If the constraint is not enforced, an error is thrown. |