Fix OSM build failure

The commit timescale#6513 removed some restricted chunk operations, enabling
adding constraints to OSM chunks directly. This operation is blocked
on OSM chunks. The present commit ensures that adding a constraint
directly on an OSM chunk is blocked.

src/process_utility.c

@@ -143,7 +143,6 @@ check_chunk_alter_table_operation_allowed(Oid relid, AlterTableStmt *stmt)
 
 			switch (cmd->subtype)
 			{
-				case AT_AddConstraint:
 				case AT_SetOptions:
 				case AT_ResetOptions:
 				case AT_SetRelOptions:
@@ -162,6 +161,18 @@ check_chunk_alter_table_operation_allowed(Oid relid, AlterTableStmt *stmt)
 #endif
 					/* allowed on chunks */
 					break;
+				case AT_AddConstraint:
+				{
+					/* if this is an OSM chunk, block the operation */
+					Chunk *chunk = ts_chunk_get_by_relid(relid, false /* fail_if_not_found */);
+					if (chunk && chunk->fd.osm_chunk)
+					{
+						ereport(ERROR,
+								(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								 errmsg("operation not supported on OSM chunk tables")));
+					}
+					break;
+				}
 				default:
 					/* disable by default */
 					all_allowed = false;

tsl/test/expected/chunk_utils_internal.out

@@ -1330,6 +1330,10 @@ SELECT * FROM test_chunkapp ORDER BY 1;
  Thu Jan 02 01:00:00 2020 PST | 2
 (2 rows)
 
+\set ON_ERROR_STOP 0
+ALTER TABLE test_chunkapp_fdw_child ADD CHECK (a > 0);
+ERROR:  operation not supported on OSM chunk tables
+\set ON_ERROR_STOP 1
 -- test error is triggered when time dimension not found
 CREATE TABLE test2(time timestamptz not null, a int);
 SELECT create_hypertable('test2', 'time');

tsl/test/sql/chunk_utils_internal.sql

@@ -704,6 +704,10 @@ SELECT _timescaledb_functions.hypertable_osm_range_update('test_chunkapp', NULL:
 EXPLAIN SELECT * FROM test_chunkapp ORDER BY 1;
 SELECT * FROM test_chunkapp ORDER BY 1;
 
+\set ON_ERROR_STOP 0
+ALTER TABLE test_chunkapp_fdw_child ADD CHECK (a > 0);
+\set ON_ERROR_STOP 1
+
 -- test error is triggered when time dimension not found
 CREATE TABLE test2(time timestamptz not null, a int);
 SELECT create_hypertable('test2', 'time');