tests for zero partitions case

Author: zilder

init.sql

@@ -72,6 +72,15 @@ SELECT pg_catalog.pg_extension_config_dump('@extschema@.pathman_config_params',
 CREATE OR REPLACE FUNCTION @extschema@.invalidate_relcache(relid OID)
 RETURNS VOID AS 'pg_pathman' LANGUAGE C STRICT;
 
+CREATE OR REPLACE FUNCTION @extschema@.partitions_count(relation REGCLASS)
+RETURNS INT AS
+$$
+BEGIN
+	RETURN count(*) FROM pg_inherits WHERE inhparent = relation;
+END
+$$
+LANGUAGE plpgsql;
+
 /* Include parent relation into query plan's for specified relation */
 CREATE OR REPLACE FUNCTION @extschema@.enable_parent(relation REGCLASS)
 RETURNS VOID AS

range.sql

@@ -59,6 +59,10 @@ BEGIN
 	p_attribute := lower(p_attribute);
 	PERFORM @extschema@.common_relation_checks(parent_relid, p_attribute);
 
+	IF p_count < 0 THEN
+		RAISE EXCEPTION 'Partitions count must not be less than zero';
+	END IF;
+
 	/* Try to determine partitions count if not set */
 	IF p_count IS NULL THEN
 		EXECUTE format('SELECT count(*), max(%s) FROM %s', p_attribute, parent_relid)
@@ -76,13 +80,19 @@ BEGIN
 		END LOOP;
 	END IF;
 
-	/* Check boundaries */
-	EXECUTE format('SELECT @extschema@.check_boundaries(''%s'', ''%s'', ''%s'', ''%s''::%s)',
-				   parent_relid,
-				   p_attribute,
-				   p_start_value,
-				   p_start_value + p_interval * p_count,
-				   pg_typeof(p_start_value));
+	/*
+	 * In case when user doesn't want to automatically create partitions
+	 * and specifies partition count as 0 then do not check boundaries
+	 */
+	IF p_count != 0 THEN
+		/* Check boundaries */
+		EXECUTE format('SELECT @extschema@.check_boundaries(''%s'', ''%s'', ''%s'', ''%s''::%s)',
+					   parent_relid,
+					   p_attribute,
+					   p_start_value,
+					   p_start_value + p_interval * p_count,
+					   pg_typeof(p_start_value));
+	END IF;
 
 	SELECT * INTO v_plain_schema, v_plain_relname
 	FROM @extschema@.get_plain_schema_and_relname(parent_relid);
@@ -147,8 +157,8 @@ BEGIN
 	p_attribute := lower(p_attribute);
 	PERFORM @extschema@.common_relation_checks(parent_relid, p_attribute);
 
-	IF p_count <= 0 THEN
-		RAISE EXCEPTION 'Partitions count must be greater than zero';
+	IF p_count < 0 THEN
+		RAISE EXCEPTION 'Partitions count must not be less than zero';
 	END IF;
 
 	/* Try to determine partitions count if not set */
@@ -172,11 +182,17 @@ BEGIN
 		END LOOP;
 	END IF;
 
-	/* check boundaries */
-	PERFORM @extschema@.check_boundaries(parent_relid,
-										 p_attribute,
-										 p_start_value,
-										 p_start_value + p_interval * p_count);
+	/*
+	 * In case when user doesn't want to automatically create partitions
+	 * and specifies partition count as 0 then do not check boundaries
+	 */
+	IF p_count != 0 THEN
+		/* check boundaries */
+		PERFORM @extschema@.check_boundaries(parent_relid,
+											 p_attribute,
+											 p_start_value,
+											 p_start_value + p_interval * p_count);
+	END IF;
 
 	SELECT * INTO v_plain_schema, v_plain_relname
 	FROM @extschema@.get_plain_schema_and_relname(parent_relid);
@@ -521,7 +537,8 @@ BEGIN
 	v_new_partition := @extschema@.create_single_range_partition(
 							@extschema@.get_schema_qualified_name(v_parent_relid),
 							p_value,
-							p_range[2]);
+							p_range[2],
+							partition_name);
 
 	/* Copy data */
 	v_cond := @extschema@.build_range_condition(v_attname, p_value, p_range[2]);
@@ -736,6 +753,10 @@ DECLARE
 	v_part_name	TEXT;
 
 BEGIN
+	IF @extschema@.partitions_count(parent_relid) = 0 THEN
+		RAISE EXCEPTION 'Cannot append to empty partitions set';
+	END IF;
+
 	p_range := @extschema@.get_range_by_idx(parent_relid, -1, 0);
 
 	IF @extschema@.is_date_type(p_atttype::regtype) THEN
@@ -825,6 +846,10 @@ DECLARE
 	v_part_name		TEXT;
 
 BEGIN
+	IF @extschema@.partitions_count(parent_relid) = 0 THEN
+		RAISE EXCEPTION 'Cannot prepend to empty partitions set';
+	END IF;
+
 	p_range := @extschema@.get_range_by_idx(parent_relid, 0, 0);
 
 	IF @extschema@.is_date_type(p_atttype::regtype) THEN
@@ -865,17 +890,17 @@ RETURNS TEXT AS
 $$
 DECLARE
 	v_part_name		TEXT;
-
 BEGIN
-	/* check range overlap */
-	IF @extschema@.check_overlap(parent_relid, p_start_value, p_end_value) THEN
-		RAISE EXCEPTION 'Specified range overlaps with existing partitions';
-	END IF;
-
 	IF p_start_value >= p_end_value THEN
 		RAISE EXCEPTION 'Failed to create partition: p_start_value is greater than p_end_value';
 	END IF;
 
+	/* check range overlap */
+	IF @extschema@.partitions_count(parent_relid) > 0
+	   AND @extschema@.check_overlap(parent_relid, p_start_value, p_end_value) THEN
+		RAISE EXCEPTION 'Specified range overlaps with existing partitions';
+	END IF;
+
 	/* Create new partition */
 	v_part_name :=@extschema@.create_single_range_partition(
 		parent_relid,

sql/pg_pathman.sql

@@ -471,6 +471,21 @@ CREATE TABLE test.range_rel_test2 (
 	dt  TIMESTAMP);
 SELECT pathman.attach_range_partition('test.range_rel', 'test.range_rel_test2', '2013-01-01'::DATE, '2014-01-01'::DATE);
 
+/*
+ * Zero partitions count and adding partitions with specified name
+ */
+CREATE TABLE test.zero(
+	id		SERIAL PRIMARY KEY,
+	value	INT NOT NULL);
+INSERT INTO test.zero SELECT g, g FROM generate_series(1, 100) as g;
+SELECT pathman.create_range_partitions('test.zero', 'value', 50, 10, 0);
+SELECT pathman.append_range_partition('test.zero', 'test.zero_0');
+SELECT pathman.prepend_range_partition('test.zero', 'test.zero_1');
+SELECT pathman.add_range_partition('test.zero', 50, 70, 'test.zero_50');
+SELECT pathman.append_range_partition('test.zero', 'test.zero_appended');
+SELECT pathman.prepend_range_partition('test.zero', 'test.zero_prepended');
+SELECT pathman.split_range_partition('test.zero_50', 60, 'test.zero_60');
+
 /*
  * Check that altering table columns doesn't break trigger
  */

src/pl_funcs.c

@@ -96,10 +96,12 @@ on_partitions_created_internal(Oid partitioned_table, bool add_callbacks)
 static void
 on_partitions_updated_internal(Oid partitioned_table, bool add_callbacks)
 {
-	/* TODO: shall we emit relcache invalidation event here? */
+	bool found;
+
 	elog(DEBUG2, "on_partitions_updated() [add_callbacks = %s] "
 				 "triggered for relation %u",
 		 (add_callbacks ? "true" : "false"), partitioned_table);
+	invalidate_pathman_relation_info(partitioned_table, &found);
 }
 
 static void

src/worker.c

@@ -498,6 +498,7 @@ partition_data_bg_worker_main(Datum main_arg)
 		SPI_connect();
 		PushActiveSnapshot(GetTransactionSnapshot());
 
+		/* Do some preparation within the first iteration */
 		if (sql == NULL)
 		{
 			MemoryContext oldcontext;
@@ -530,10 +531,12 @@ partition_data_bg_worker_main(Datum main_arg)
 		}
 		PG_CATCH();
 		{
+			ErrorData *error;
 			EmitErrorReport();
+			error = CopyErrorData();
+			elog(LOG, "Worker error: %s", error->message);
 			FlushErrorState();
 
-			elog(WARNING, "Error #%u", failures_count);
 			/*
 			 * The most common exception we can catch here is a deadlock with
 			 * concurrent user queries. Check that attempts count doesn't exceed
@@ -543,7 +546,9 @@ partition_data_bg_worker_main(Datum main_arg)
 			{
 				pfree(sql);
 				args->status = WS_FREE;
-				elog(ERROR, "Failures count exceeded 100. Finishing...");
+				elog(LOG,
+					 "The concurrent partitioning worker exiting because the "
+					 "maximum attempts count exceeded. See the error message below");
 				exit(1);
 			}
 			failed = true;