Expose some functions to support PAX for partition tables

1. ComputePartitionAttrs: expose function
2. transformPartitionBound: add argument of PartitionKey
3. transformPartitionRangeBounds: add argument of PartitionKey
4. list_sort_arg: sort the List with context argument in cmp function

src/backend/commands/tablecmds.c

@@ -533,8 +533,6 @@ static void ATExecExpandTableCTAS(AlterTableCmd *rootCmd, Relation rel, AlterTab
 static void ATExecSetDistributedBy(Relation rel, Node *node,
 								   AlterTableCmd *cmd);
 static PartitionSpec *transformPartitionSpec(Relation rel, PartitionSpec *partspec, char *strategy);
-static void ComputePartitionAttrs(ParseState *pstate, Relation rel, List *partParams, AttrNumber *partattrs,
-								  List **partexprs, Oid *partopclass, Oid *partcollation, char strategy);
 static void CreateInheritance(Relation child_rel, Relation parent_rel);
 static void RemoveInheritance(Relation child_rel, Relation parent_rel,
 							  bool allow_detached);
@@ -1241,7 +1239,7 @@ DefineRelation(CreateStmt *stmt, char relkind, Oid ownerId,
 											   NULL, false, false);
 		addNSItemToQuery(pstate, nsitem, false, true, true);
 
-		bound = transformPartitionBound(pstate, parent, stmt->partbound);
+		bound = transformPartitionBound(pstate, parent, RelationGetPartitionKey(parent), stmt->partbound);
 
 		/*
 		 * Check first that the new partition's bound is valid and does not
@@ -20435,7 +20433,7 @@ transformPartitionSpec(Relation rel, PartitionSpec *partspec, char *strategy)
  * Compute per-partition-column information from a list of PartitionElems.
  * Expressions in the PartitionElems must be parse-analyzed already.
  */
-static void
+void
 ComputePartitionAttrs(ParseState *pstate, Relation rel, List *partParams, AttrNumber *partattrs,
 					  List **partexprs, Oid *partopclass, Oid *partcollation,
 					  char strategy)

src/backend/nodes/list.c

@@ -1572,6 +1572,20 @@ list_sort(List *list, list_sort_comparator cmp)
 		qsort(list->elements, len, sizeof(ListCell), (qsort_comparator) cmp);
 }
 
+void
+list_sort_arg(List *list, list_sort_arg_comparator cmp, void *arg)
+{
+	typedef int (*qsort_arg_comparator) (const void *a, const void *b, void *arg);
+	int			len;
+
+	check_list_invariants(list);
+
+	/* Nothing to do if there's less than two elements */
+	len = list_length(list);
+	if (len > 1)
+		qsort_arg(list->elements, len, sizeof(ListCell), (qsort_arg_comparator) cmp, arg);
+}
+
 /*
  * list_sort comparator for sorting a list into ascending int order.
  */

src/backend/parser/parse_partition_gp.c

@@ -85,11 +85,11 @@ static char *extract_tablename_from_options(List **options);
  * Used when sorting CreateStmts across all partitions.
  */
 static int32
-qsort_stmt_cmp(const void *a, const void *b, void *arg)
+qsort_stmt_cmp(const ListCell *a, const ListCell *b, void *arg)
 {
 	int32		cmpval = 0;
-	CreateStmt	   *b1cstmt = *(CreateStmt **) a;
-	CreateStmt	   *b2cstmt = *(CreateStmt **) b;
+	CreateStmt	   *b1cstmt = lfirst_node(CreateStmt, a);
+	CreateStmt	   *b2cstmt = lfirst_node(CreateStmt, b);
 	PartitionKey partKey = (PartitionKey) arg;
 	PartitionBoundSpec *b1 = b1cstmt->partbound;
 	PartitionBoundSpec *b2 = b2cstmt->partbound;
@@ -317,36 +317,6 @@ consts_to_datums(PartitionKey partkey, List *consts)
 	return datums;
 }
 
-/*
- * Sort a list of CreateStmts in-place.
- */
-static void
-list_qsort_arg(List *list, qsort_arg_comparator cmp, void *arg)
-{
-	int			len = list_length(list);
-	ListCell   *cell;
-	CreateStmt **create_stmts;
-	int			i;
-
-	/* Empty list is easy */
-	if (len == 0)
-		return;
-
-	/* Flatten list into an array, so we can use qsort */
-	create_stmts = (CreateStmt **) palloc(sizeof(CreateStmt *) * len);
-	i = 0;
-	foreach(cell, list)
-		create_stmts[i++] = (CreateStmt *) lfirst(cell);
-
-	qsort_arg(create_stmts, len, sizeof(CreateStmt *), cmp, arg);
-
-	i = 0;
-	foreach(cell, list)
-		cell->ptr_value = create_stmts[i++];
-
-	pfree(create_stmts);
-}
-
 /*
  * Sort the list of GpPartitionBoundSpecs based first on START, if START does
  * not exist, use END. After sort, if any stmt contains an implicit START or
@@ -359,7 +329,7 @@ deduceImplicitRangeBounds(ParseState *pstate, Relation parentrel, List *stmts)
 	/* GPDB_14_MERGE_FIXEME: most places use true for new api, need to check */
 	PartitionDesc desc = RelationGetPartitionDesc(parentrel, true);
 
-	list_qsort_arg(stmts, qsort_stmt_cmp, key);
+	list_sort_arg(stmts, qsort_stmt_cmp, key);
 
 	/*
 	 * This works slightly differenly, depending on whether this is a
@@ -1111,7 +1081,7 @@ generateListPartition(ParseState *pstate,
 	boundspec->listdatums = listdatums;
 	boundspec->location = -1;
 
-	boundspec = transformPartitionBound(pstate, parentrel, boundspec);
+	boundspec = transformPartitionBound(pstate, parentrel, RelationGetPartitionKey(parentrel), boundspec);
 	childstmt = makePartitionCreateStmt(parentrel, elem->partName, boundspec, subPart,
 										elem, partnamecomp);
 

src/backend/parser/parse_utilcmd.c

@@ -155,7 +155,7 @@ static void transformColumnType(CreateStmtContext *cxt, ColumnDef *column);
 static void setSchemaName(char *context_schema, char **stmt_schema_name);
 static void transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd);
 static List *transformPartitionRangeBounds(ParseState *pstate, List *blist,
-										   Relation parent);
+										   Relation parent, PartitionKey key);
 static void validateInfiniteBounds(ParseState *pstate, List *blist);
 
 static DistributedBy *getLikeDistributionPolicy(TableLikeClause *e);
@@ -5127,7 +5127,7 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
 			Assert(RelationGetPartitionKey(parentRel) != NULL);
 			if (cmd->bound != NULL)
 				cxt->partbound = transformPartitionBound(cxt->pstate, parentRel,
-														 cmd->bound);
+														 RelationGetPartitionKey(parentRel), cmd->bound);
 			break;
 		case RELKIND_PARTITIONED_INDEX:
 
@@ -5169,11 +5169,10 @@ transformPartitionCmd(CreateStmtContext *cxt, PartitionCmd *cmd)
  * Transform a partition bound specification
  */
 PartitionBoundSpec *
-transformPartitionBound(ParseState *pstate, Relation parent,
+transformPartitionBound(ParseState *pstate, Relation parent, PartitionKey key,
 						PartitionBoundSpec *spec)
 {
 	PartitionBoundSpec *result_spec;
-	PartitionKey key = RelationGetPartitionKey(parent);
 	char		strategy = get_partition_strategy(key);
 	int			partnatts = get_partition_natts(key);
 	List	   *partexprs = get_partition_exprs(key);
@@ -5306,10 +5305,10 @@ transformPartitionBound(ParseState *pstate, Relation parent,
 		 */
 		result_spec->lowerdatums =
 			transformPartitionRangeBounds(pstate, spec->lowerdatums,
-										  parent);
+										  parent, key);
 		result_spec->upperdatums =
 			transformPartitionRangeBounds(pstate, spec->upperdatums,
-										  parent);
+										  parent, key);
 	}
 	else
 		elog(ERROR, "unexpected partition strategy: %d", (int) strategy);
@@ -5324,10 +5323,9 @@ transformPartitionBound(ParseState *pstate, Relation parent,
  */
 static List *
 transformPartitionRangeBounds(ParseState *pstate, List *blist,
-							  Relation parent)
+							  Relation parent, PartitionKey key)
 {
 	List	   *result = NIL;
-	PartitionKey key = RelationGetPartitionKey(parent);
 	List	   *partexprs = get_partition_exprs(key);
 	ListCell   *lc;
 	int			i,

src/include/commands/tablecmds.h

@@ -124,6 +124,8 @@ extern void RangeVarCallbackOwnsRelation(const RangeVar *relation,
 										 Oid relId, Oid oldRelId, void *arg);
 extern bool PartConstraintImpliedByRelConstraint(Relation scanrel,
 												 List *partConstraint);
+extern void ComputePartitionAttrs(ParseState *pstate, Relation rel, List *partParams, AttrNumber *partattrs,
+								  List **partexprs, Oid *partopclass, Oid *partcollation, char strategy);
 
 /* GPDB specific functions */
 extern void ATExecGPPartCmds(Relation origrel, AlterTableCmd *cmd);

src/include/nodes/pg_list.h

@@ -627,6 +627,9 @@ extern pg_nodiscard List *list_copy_deep(const List *oldlist);
 typedef int (*list_sort_comparator) (const ListCell *a, const ListCell *b);
 extern void list_sort(List *list, list_sort_comparator cmp);
 
+typedef int (*list_sort_arg_comparator) (const ListCell *a, const ListCell *b, void *arg);
+extern void list_sort_arg(List *list, list_sort_arg_comparator cmp, void *arg);
+
 extern int	list_int_cmp(const ListCell *p1, const ListCell *p2);
 extern int	list_oid_cmp(const ListCell *p1, const ListCell *p2);
 

src/include/parser/parse_utilcmd.h

@@ -35,7 +35,7 @@ extern void transformRuleStmt(RuleStmt *stmt, const char *queryString,
 							  List **actions, Node **whereClause);
 extern List *transformCreateSchemaStmt(CreateSchemaStmt *stmt);
 extern PartitionBoundSpec *transformPartitionBound(ParseState *pstate, Relation parent,
-												   PartitionBoundSpec *spec);
+												   PartitionKey key, PartitionBoundSpec *spec);
 extern List *expandTableLikeClause(RangeVar *heapRel,
 								   TableLikeClause *table_like_clause);
 extern IndexStmt *generateClonedIndexStmt(RangeVar *heapRel,