pathman: copy data before dropping partitions

zilder · zilder · commit 1e178f03d1f8 · 2016-02-12T13:21:12.000+03:00
diff --git a/contrib/pg_pathman/expected/pg_pathman.out b/contrib/pg_pathman/expected/pg_pathman.out
@@ -481,9 +481,15 @@ NOTICE:  function test.hash_rel_hash_update_trigger_func() does not exist, skipp
 
 DROP TABLE test.hash_rel CASCADE;
 SELECT pathman.drop_range_partitions('test.num_range_rel');
+NOTICE:  0 rows copied from test.num_range_rel_7
+NOTICE:  0 rows copied from test.num_range_rel_6
+NOTICE:  2 rows copied from test.num_range_rel_4
+NOTICE:  1000 rows copied from test.num_range_rel_3
+NOTICE:  1000 rows copied from test.num_range_rel_2
+NOTICE:  998 rows copied from test.num_range_rel_1
  drop_range_partitions 
 -----------------------
- 
+                     6
 (1 row)
 
 DROP TABLE test.num_range_rel CASCADE;
@@ -668,9 +674,24 @@ EXPLAIN (COSTS OFF) SELECT * FROM range_rel WHERE dt < '2010-03-01';
 
 /* Create range partitions from whole range */
 SELECT drop_range_partitions('range_rel');
+NOTICE:  0 rows copied from range_rel_archive
+NOTICE:  0 rows copied from range_rel_15
+NOTICE:  0 rows copied from range_rel_14
+NOTICE:  14 rows copied from range_rel_13
+NOTICE:  31 rows copied from range_rel_12
+NOTICE:  30 rows copied from range_rel_11
+NOTICE:  31 rows copied from range_rel_10
+NOTICE:  30 rows copied from range_rel_9
+NOTICE:  31 rows copied from range_rel_8
+NOTICE:  31 rows copied from range_rel_7
+NOTICE:  30 rows copied from range_rel_6
+NOTICE:  31 rows copied from range_rel_5
+NOTICE:  30 rows copied from range_rel_4
+NOTICE:  31 rows copied from range_rel_3
+NOTICE:  45 rows copied from range_rel_1
  drop_range_partitions 
 -----------------------
- 
+                    15
 (1 row)
 
 SELECT create_partitions_from_range('range_rel', 'id', 1, 1000, 100);
@@ -681,9 +702,19 @@ NOTICE:  Copying data to partitions...
 (1 row)
 
 SELECT drop_range_partitions('range_rel');
+NOTICE:  0 rows copied from range_rel_10
+NOTICE:  0 rows copied from range_rel_9
+NOTICE:  0 rows copied from range_rel_8
+NOTICE:  0 rows copied from range_rel_7
+NOTICE:  0 rows copied from range_rel_6
+NOTICE:  0 rows copied from range_rel_5
+NOTICE:  65 rows copied from range_rel_4
+NOTICE:  100 rows copied from range_rel_3
+NOTICE:  100 rows copied from range_rel_2
+NOTICE:  100 rows copied from range_rel_1
  drop_range_partitions 
 -----------------------
- 
+                    10
 (1 row)
 
 SELECT create_partitions_from_range('range_rel', 'dt', '2015-01-01'::date, '2015-12-01'::date, '1 month'::interval);
diff --git a/contrib/pg_pathman/range.sql b/contrib/pg_pathman/range.sql
@@ -719,27 +719,39 @@ $$ LANGUAGE plpgsql;
  * Drop partitions
  */
 CREATE OR REPLACE FUNCTION @extschema@.drop_range_partitions(IN relation TEXT)
-RETURNS VOID AS
+RETURNS INTEGER AS
 $$
 DECLARE
     v_rec   RECORD;
+    -- v_total_rows INTEGER;
+    v_rows INTEGER;
+    v_part_count INTEGER := 0;
 BEGIN
     relation := @extschema@.validate_relname(relation);
 
     /* Drop trigger first */
     PERFORM @extschema@.drop_range_triggers(relation);
 
-    FOR v_rec IN (SELECT inhrelid::regclass AS tbl
+    FOR v_rec IN (SELECT inhrelid::regclass::text AS tbl
                   FROM pg_inherits WHERE inhparent = relation::regclass::oid)
     LOOP
+        EXECUTE format('WITH part_data AS (DELETE FROM %s RETURNING *)
+                        INSERT INTO %s SELECT * FROM part_data'
+                       , v_rec.tbl
+                       , relation);
+        GET DIAGNOSTICS v_rows = ROW_COUNT;
         EXECUTE format('DROP TABLE %s', v_rec.tbl);
+        RAISE NOTICE '% rows copied from %', v_rows, v_rec.tbl;
+        v_part_count := v_part_count + 1;
     END LOOP;
 
     DELETE FROM @extschema@.pathman_config WHERE relname = relation;
     -- DELETE FROM pg_pathman_range_rels WHERE parent = relation;
 
     /* Notify backend about changes */
     PERFORM @extschema@.on_remove_partitions(relation::regclass::oid);
+
+    RETURN v_part_count;
 END
 $$ LANGUAGE plpgsql;
 
