partition-bound-collation-check.patch

diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 164312d..68a8a03 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -4172,6 +4172,7 @@ transformPartitionBoundValue(ParseState *pstate, Node *val,
 							 Oid partCollation)
 {
 	Node	   *value;
+	Oid			exprCollOid;
 
 	/* Transform raw parsetree */
 	value = transformExpr(pstate, val, EXPR_KIND_PARTITION_BOUND);
@@ -4184,50 +4185,6 @@ transformPartitionBoundValue(ParseState *pstate, Node *val,
 	Assert(!contain_var_clause(value));
 
 	/*
-	 * Check that the input expression's collation is compatible with one
-	 * specified for the parent's partition key (partcollation).  Don't throw
-	 * an error if it's the default collation which we'll replace with the
-	 * parent's collation anyway.
-	 */
-	if (IsA(value, CollateExpr))
-	{
-		Oid			exprCollOid = exprCollation(value);
-
-		/*
-		 * Check we have a collation iff it is a collatable type.  The only
-		 * expected failures here are (1) COLLATE applied to a noncollatable
-		 * type, or (2) partition bound expression had an unresolved
-		 * collation.  But we might as well code this to be a complete
-		 * consistency check.
-		 */
-		if (type_is_collatable(colType))
-		{
-			if (!OidIsValid(exprCollOid))
-				ereport(ERROR,
-						(errcode(ERRCODE_INDETERMINATE_COLLATION),
-						 errmsg("could not determine which collation to use for partition bound expression"),
-						 errhint("Use the COLLATE clause to set the collation explicitly.")));
-		}
-		else
-		{
-			if (OidIsValid(exprCollOid))
-				ereport(ERROR,
-						(errcode(ERRCODE_DATATYPE_MISMATCH),
-						 errmsg("collations are not supported by type %s",
-								format_type_be(colType))));
-		}
-
-		if (OidIsValid(exprCollOid) &&
-			exprCollOid != DEFAULT_COLLATION_OID &&
-			exprCollOid != partCollation)
-			ereport(ERROR,
-					(errcode(ERRCODE_DATATYPE_MISMATCH),
-					 errmsg("collation of partition bound value for column \"%s\" does not match partition key collation \"%s\"",
-							colName, get_collation_name(partCollation)),
-					 parser_errposition(pstate, exprLocation(value))));
-	}
-
-	/*
 	 * Coerce to the correct type.  This might cause an explicit coercion step
 	 * to be added on top of the expression, which must be evaluated before
 	 * returning the result to the caller.
@@ -4247,6 +4204,35 @@ transformPartitionBoundValue(ParseState *pstate, Node *val,
 						format_type_be(colType), colName),
 				 parser_errposition(pstate, exprLocation(val))));
 
+	/* Fix up collation information */
+	assign_expr_collations(pstate, value);
+
+	/*
+	 * Check that the input expression's assigned collation is compatible with
+	 * one specified for the parent's partition key (partcollation).  Don't
+	 * throw an error if it's the default collation which we'll replace with
+	 * the parent's collation anyway.
+	 */
+	exprCollOid = exprCollation(value);
+
+	/* Complain if COLLATE seems to be applied to an uncollatable type. */
+	if (!type_is_collatable(colType) && OidIsValid(exprCollOid))
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("collations are not supported by type %s",
+						format_type_be(colType))));
+
+	if (OidIsValid(exprCollOid) &&
+		exprCollOid != DEFAULT_COLLATION_OID &&
+		exprCollOid != partCollation)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("collation of partition bound value for column \"%s\" does not match partition key collation \"%s\"",
+						colName, get_collation_name(partCollation)),
+						parser_errposition(pstate, exprLocation(value)),
+				 errdetail("The collation of partition bound value is \"%s\".",
+						   get_collation_name(exprCollOid))));
+
 	/*
 	 * Evaluate the expression, if needed, assigning the partition key's data
 	 * type and collation to the resulting Const node.
diff --git a/src/test/regress/expected/create_table.out b/src/test/regress/expected/create_table.out
index 41dce69..ec900ac 100644
--- a/src/test/regress/expected/create_table.out
+++ b/src/test/regress/expected/create_table.out
@@ -1034,6 +1034,7 @@ create table test_part_coll partition of test_part_coll_posix for values from ('
 ERROR:  collation of partition bound value for column "a" does not match partition key collation "POSIX"
 LINE 1: ...artition of test_part_coll_posix for values from ('a' collat...
                                                              ^
+DETAIL:  The collation of partition bound value is "C".
 -- ok
 create table test_part_coll partition of test_part_coll_posix for values from ('a' collate "POSIX") to ('g');
 -- ok
@@ -1044,10 +1045,15 @@ create table test_part_coll_cast partition of test_part_coll_posix for values fr
 ERROR:  collation of partition bound value for column "a" does not match partition key collation "POSIX"
 LINE 1: ...ion of test_part_coll_posix for values from (name 'm' collat...
                                                              ^
+DETAIL:  The collation of partition bound value is "C".
 -- ok
 create table test_part_coll_cast partition of test_part_coll_posix for values from (name 'm' collate "POSIX") to ('s');
 -- ok; partition collation silently overrides the default collation of type 'name'
 create table test_part_coll_cast2 partition of test_part_coll_posix for values from (name 's') to ('z');
+ERROR:  collation of partition bound value for column "a" does not match partition key collation "POSIX"
+LINE 1: ...ion of test_part_coll_posix for values from (name 's') to ('...
+                                                             ^
+DETAIL:  The collation of partition bound value is "C".
 drop table test_part_coll_posix;
 -- Partition bound in describe output
 \d+ part_b