Simplify add_to_pathman_config, check hash function for expression for hash partitioning type.

Author: ildus

expected/pathman_permissions.out

@@ -19,6 +19,7 @@ GRANT SELECT ON permissions.user1_table TO user2;
 /* Should fail (don't own parent) */
 SET ROLE user2;
 SELECT create_range_partitions('permissions.user1_table', 'id', 1, 10, 2);
+WARNING:  skipping "user1_table" --- only table or database owner can analyze it
 ERROR:  only the owner or superuser can change partitioning configuration of table "user1_table"
 /* Should be ok */
 SET ROLE user1;

hash.sql

@@ -35,7 +35,8 @@ BEGIN
 	PERFORM @extschema@.common_relation_checks(parent_relid, expression);
 
 	/* Insert new entry to pathman config */
-	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression, NULL, false);
+	EXECUTE format('ANALYZE %s', parent_relid);
+	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression, NULL);
 
 	/* Create partitions */
 	PERFORM @extschema@.create_hash_partitions_internal(parent_relid,

init.sql

@@ -862,9 +862,8 @@ LANGUAGE C STRICT;
  */
 CREATE OR REPLACE FUNCTION @extschema@.add_to_pathman_config(
 	parent_relid		REGCLASS,
-	attname				TEXT,
+	expression			TEXT,
 	range_interval		TEXT DEFAULT NULL,
-	refresh_part_info	BOOL DEFAULT TRUE,
 	parttype			INT4 DEFAULT 0
 )
 RETURNS BOOLEAN AS 'pg_pathman', 'add_to_pathman_config'

range.sql

@@ -154,8 +154,9 @@ BEGIN
 	END IF;
 
 	/* Insert new entry to pathman config */
+	EXECUTE format('ANALYZE %s', parent_relid);
 	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression,
-		p_interval::TEXT, false);
+		p_interval::TEXT);
 
 	/* Create sequence for child partitions names */
 	PERFORM @extschema@.create_or_replace_sequence(parent_relid);
@@ -251,8 +252,9 @@ BEGIN
 	END IF;
 
 	/* Insert new entry to pathman config */
+	EXECUTE format('ANALYZE %s', parent_relid);
 	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression,
-		p_interval::TEXT, false);
+		p_interval::TEXT);
 
 	/* Create sequence for child partitions names */
 	PERFORM @extschema@.create_or_replace_sequence(parent_relid);
@@ -310,7 +312,8 @@ BEGIN
 										 bounds[array_length(bounds, 1) - 1]);
 
 	/* Insert new entry to pathman config */
-	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression, NULL, false, 2);
+	EXECUTE format('ANALYZE %s', parent_relid);
+	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression, NULL, 2);
 
 	/* Create sequence for child partitions names */
 	PERFORM @extschema@.create_or_replace_sequence(parent_relid);
@@ -360,8 +363,9 @@ BEGIN
 										 end_value);
 
 	/* Insert new entry to pathman config */
+	EXECUTE format('ANALYZE %s', parent_relid);
 	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression,
-		p_interval::TEXT, false);
+		p_interval::TEXT);
 
 	/* Create sequence for child partitions names */
 	PERFORM @extschema@.create_or_replace_sequence(parent_relid);
@@ -417,8 +421,9 @@ BEGIN
 										 end_value);
 
 	/* Insert new entry to pathman config */
+	EXECUTE format('ANALYZE %s', parent_relid);
 	PERFORM @extschema@.add_to_pathman_config(parent_relid, expression,
-		p_interval::TEXT, false);
+		p_interval::TEXT);
 
 	/* Create sequence for child partitions names */
 	PERFORM @extschema@.create_or_replace_sequence(parent_relid);

src/pl_funcs.c

@@ -22,6 +22,7 @@
 #include "access/nbtree.h"
 #include "access/htup_details.h"
 #include "catalog/indexing.h"
+#include "catalog/pg_inherits_fn.h"
 #include "catalog/pg_trigger.h"
 #include "catalog/pg_type.h"
 #include "commands/tablespace.h"
@@ -709,7 +710,6 @@ add_to_pathman_config(PG_FUNCTION_ARGS)
 	Relation			pathman_config;
 	Datum				values[Natts_pathman_config];
 	bool				isnull[Natts_pathman_config];
-	bool				refresh_part_info;
 	HeapTuple			htup;
 
 	Oid					expr_type;
@@ -745,13 +745,23 @@ add_to_pathman_config(PG_FUNCTION_ARGS)
 	}
 
 	/* Select partitioning type */
-	parttype = PG_GETARG_INT32(4);
+	parttype = PG_GETARG_INT32(3);
 	if ((parttype != PT_HASH) && (parttype != PT_RANGE))
 		parttype = PG_ARGISNULL(2) ? PT_HASH : PT_RANGE;
 
 	/* Parse and check expression */
 	expr_datum = plan_partitioning_expression(relid, expression, &expr_type);
 
+	/* Expression for range partitions should be hashable */
+	if (parttype == PT_HASH)
+	{
+		TypeCacheEntry *tce;
+
+		tce = lookup_type_cache(expr_type, TYPECACHE_HASH_PROC);
+		if (tce->hash_proc == InvalidOid)
+			elog(ERROR, "partitioning expression should be hashable");
+	}
+
 	/*
 	 * Initialize columns (partrel, attname, parttype, range_interval).
 	 */
@@ -790,10 +800,8 @@ add_to_pathman_config(PG_FUNCTION_ARGS)
 
 	heap_close(pathman_config, RowExclusiveLock);
 
-	/* FIXME: check pg_inherits instead of this argument */
-	refresh_part_info = PG_GETARG_BOOL(3);
-
-	if (refresh_part_info)
+	/* update caches only if this relation has children */
+	if (has_subclass(relid))
 	{
 		/* Now try to create a PartRelationInfo */
 		PG_TRY();