Fix assignment to array of domain over composite, redux.

Commit 3e310d837 taught isAssignmentIndirectionExpr() to look through
CoerceToDomain nodes.  That's not sufficient, because since commit
04fe805a1 it's been possible for the planner to simplify
CoerceToDomain to RelabelType when the domain has no constraints
to enforce.  So we need to look through RelabelType too.

Per bug #17897 from Alexander Lakhin.  Although 3e310d837 was
back-patched to v11, it seems sufficient to apply this change
to v12 and later, since 04fe805a1 came in in v12.

Dmitry Dolgov

Discussion: https://postgr.es/m/17897-4216c546c3874044@postgresql.org

diff --git a/src/backend/executor/execExpr.c b/src/backend/executor/execExpr.c
index 4c6700de04553a436ad95b47bf8c2cdeeb406a49..dcf56446c747b36ad98fad79b2a5485ede583683 100644 (file)
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -3225,8 +3225,8 @@ ExecInitSubscriptingRef(ExprEvalStep *scratch, SubscriptingRef *sbsref,
  * trees in which each level of assignment has its own CaseTestExpr, and the
  * recursive structure appears within the newvals or refassgnexpr field.
  * There is an exception, though: if the array is an array-of-domain, we will
- * have a CoerceToDomain as the refassgnexpr, and we need to be able to look
- * through that.
+ * have a CoerceToDomain or RelabelType as the refassgnexpr, and we need to
+ * be able to look through that.
  */
 static bool
 isAssignmentIndirectionExpr(Expr *expr)
@@ -3253,6 +3253,12 @@ isAssignmentIndirectionExpr(Expr *expr)
 
                return isAssignmentIndirectionExpr(cd->arg);
        }
+       else if (IsA(expr, RelabelType))
+       {
+               RelabelType *r = (RelabelType *) expr;
+
+               return isAssignmentIndirectionExpr(r->arg);
+       }
        return false;
 }
 

diff --git a/src/test/regress/expected/domain.out b/src/test/regress/expected/domain.out
index b7937fb3bc6cf4434ca62356812c65292edde12e..6d94e84414a66b337042d9341270197746504e3d 100644 (file)
--- a/src/test/regress/expected/domain.out
+++ b/src/test/regress/expected/domain.out
@@ -606,6 +606,15 @@ table dcomptable;
  {"(1,5)"}
 (1 row)
 
+-- if there's no constraints, a different code path is taken:
+alter domain dcomptype drop constraint dcomptype_check;
+update dcomptable set f1[1].cf1 = -1;  -- now ok
+table dcomptable;
+     f1     
+------------
+ {"(-1,5)"}
+(1 row)
+
 drop table dcomptable;
 drop type comptype cascade;
 NOTICE:  drop cascades to type dcomptype

diff --git a/src/test/regress/sql/domain.sql b/src/test/regress/sql/domain.sql
index a9a56f5277ca066a99aa0a07412cecd3b119c45c..745f5d5fd2b10ce599a9b5b23adaf5aec6aa58de 100644 (file)
--- a/src/test/regress/sql/domain.sql
+++ b/src/test/regress/sql/domain.sql
@@ -307,6 +307,10 @@ table dcomptable;
 update dcomptable set f1[1].cf1 = -1;  -- fail
 update dcomptable set f1[1].cf1 = 1;
 table dcomptable;
+-- if there's no constraints, a different code path is taken:
+alter domain dcomptype drop constraint dcomptype_check;
+update dcomptable set f1[1].cf1 = -1;  -- now ok
+table dcomptable;
 
 drop table dcomptable;
 drop type comptype cascade;