diff options
| -rw-r--r-- | doc/src/sgml/ref/create_domain.sgml | 3 | ||||
| -rw-r--r-- | src/backend/optimizer/plan/initsplan.c | 14 |
2 files changed, 16 insertions, 1 deletions
diff --git a/doc/src/sgml/ref/create_domain.sgml b/doc/src/sgml/ref/create_domain.sgml index ce555203486..c111285a69c 100644 --- a/doc/src/sgml/ref/create_domain.sgml +++ b/doc/src/sgml/ref/create_domain.sgml @@ -283,7 +283,8 @@ CREATE TABLE us_snail_addy ( <para> The syntax <literal>NOT NULL</literal> in this command is a <productname>PostgreSQL</productname> extension. (A standard-conforming - way to write the same would be <literal>CHECK (VALUE IS NOT + way to write the same for non-composite data types would be + <literal>CHECK (VALUE IS NOT NULL)</literal>. However, per <xref linkend="sql-createdomain-notes"/>, such constraints are best avoided in practice anyway.) The <literal>NULL</literal> <quote>constraint</quote> is a diff --git a/src/backend/optimizer/plan/initsplan.c b/src/backend/optimizer/plan/initsplan.c index 1d1aa27d450..01804b085b3 100644 --- a/src/backend/optimizer/plan/initsplan.c +++ b/src/backend/optimizer/plan/initsplan.c @@ -3109,6 +3109,13 @@ restriction_is_always_true(PlannerInfo *root, if (nulltest->nulltesttype != IS_NOT_NULL) return false; + /* + * Empty rows can appear NULL in some contexts and NOT NULL in others, + * so avoid this optimization for row expressions. + */ + if (nulltest->argisrow) + return false; + return expr_is_nonnullable(root, nulltest->arg); } @@ -3167,6 +3174,13 @@ restriction_is_always_false(PlannerInfo *root, if (nulltest->nulltesttype != IS_NULL) return false; + /* + * Empty rows can appear NULL in some contexts and NOT NULL in others, + * so avoid this optimization for row expressions. + */ + if (nulltest->argisrow) + return false; + return expr_is_nonnullable(root, nulltest->arg); } |