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 d89445ee7ba64e4e178b5ad48d158e0ec1b3f2a1..26d7972f837d91db55d4a6cac1811fb0b0b8d4d7 100644 (file)
--- a/src/backend/executor/execExpr.c
+++ b/src/backend/executor/execExpr.c
@@ -3131,8 +3131,8 @@ 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)
@@ -3159,6 +3159,12 @@ 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 73b010f6ed28d38b0ca0c3d5156b0818db643a58..46a263533014e32ad7d0e2dabaf2ae62590b2f3e 100644 (file)
--- a/src/test/regress/expected/domain.out
+++ b/src/test/regress/expected/domain.out
@@ -556,6 +556,15 @@ 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 f2ca1fb675a0d37263f692b0a707a2c3e7ffd6e2..b735d9bfe19b44ea9f0ddb593e60bfdee262aa49 100644 (file)
--- a/src/test/regress/sql/domain.sql
+++ b/src/test/regress/sql/domain.sql
@@ -288,6 +288,10 @@ 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;