Add worker_hash() and a stub for isolate_tenant_to_new_shard()

src/backend/distributed/Makefile

@@ -9,7 +9,7 @@ EXTVERSIONS = 5.0 5.0-1 5.0-2  \
 	5.1-1 5.1-2 5.1-3 5.1-4 5.1-5 5.1-6 5.1-7 5.1-8 \
 	5.2-1 5.2-2 5.2-3 5.2-4 \
 	6.0-1 6.0-2 6.0-3 6.0-4 6.0-5 6.0-6 6.0-7 6.0-8 6.0-9 6.0-10 6.0-11 6.0-12 6.0-13 6.0-14 6.0-15 6.0-16 6.0-17 6.0-18 \
-	6.1-1 6.1-2 6.1-3 6.1-4 6.1-5 6.1-6 6.1-7 6.1-8 6.1-9 6.1-10 6.1-11 6.1-12 6.1-13 6.1-14 6.1-15 6.1-16
+	6.1-1 6.1-2 6.1-3 6.1-4 6.1-5 6.1-6 6.1-7 6.1-8 6.1-9 6.1-10 6.1-11 6.1-12 6.1-13 6.1-14 6.1-15 6.1-16 6.1-17
 
 # All citus--*.sql files in the source directory
 DATA = $(patsubst $(citus_abs_srcdir)/%.sql,%.sql,$(wildcard $(citus_abs_srcdir)/$(EXTENSION)--*--*.sql))
@@ -127,6 +127,8 @@ $(EXTENSION)--6.1-15.sql: $(EXTENSION)--6.1-14.sql $(EXTENSION)--6.1-14--6.1-15.
 	cat $^ > $@
 $(EXTENSION)--6.1-16.sql: $(EXTENSION)--6.1-15.sql $(EXTENSION)--6.1-15--6.1-16.sql
 	cat $^ > $@
+$(EXTENSION)--6.1-17.sql: $(EXTENSION)--6.1-16.sql $(EXTENSION)--6.1-16--6.1-17.sql
+	cat $^ > $@
 
 NO_PGXS = 1
 

src/backend/distributed/citus--6.1-16--6.1-17.sql

@@ -0,0 +1,19 @@
+/* citus--6.1-16--6.1-17.sql */
+
+SET search_path = 'pg_catalog';
+
+CREATE FUNCTION isolate_tenant_to_new_shard(table_name regclass, tenant_id "any", cascade_option text DEFAULT '')
+	RETURNS bigint
+    LANGUAGE C STRICT
+    AS 'MODULE_PATHNAME', $$isolate_tenant_to_new_shard$$;
+COMMENT ON FUNCTION isolate_tenant_to_new_shard(table_name regclass, tenant_id "any", cascade_option text)
+    IS 'isolate a tenant to its own shard and return the new shard id';
+
+CREATE FUNCTION worker_hash(value "any")
+	RETURNS integer
+    LANGUAGE C STRICT
+    AS 'MODULE_PATHNAME', $$worker_hash$$;
+COMMENT ON FUNCTION worker_hash(value "any")
+    IS 'calculate hashed value and return it';
+
+RESET search_path;

src/backend/distributed/citus.control

@@ -1,6 +1,6 @@
 # Citus extension
 comment = 'Citus distributed database'
-default_version = '6.1-16'
+default_version = '6.1-17'
 module_pathname = '$libdir/citus'
 relocatable = false
 schema = pg_catalog

src/backend/distributed/master/master_split_shards.c

@@ -0,0 +1,89 @@
+/*-------------------------------------------------------------------------
+ *
+ * master_split_shards.c
+ *
+ * This file contains functions to split a shard according to a given
+ * distribution column value.
+ *
+ * Copyright (c) 2014-2017, Citus Data, Inc.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+#include "c.h"
+#include "fmgr.h"
+
+#include "catalog/pg_class.h"
+#include "distributed/colocation_utils.h"
+#include "distributed/connection_cache.h"
+#include "distributed/master_protocol.h"
+#include "distributed/metadata_cache.h"
+#include "distributed/metadata_sync.h"
+#include "distributed/multi_join_order.h"
+#include "distributed/multi_router_planner.h"
+#include "distributed/pg_dist_partition.h"
+#include "distributed/pg_dist_shard.h"
+#include "distributed/remote_commands.h"
+#include "distributed/resource_lock.h"
+#include "distributed/worker_manager.h"
+#include "distributed/worker_protocol.h"
+#include "distributed/worker_transaction.h"
+#include "nodes/pg_list.h"
+#include "storage/lock.h"
+#include "utils/builtins.h"
+#include "utils/elog.h"
+#include "utils/errcodes.h"
+#include "utils/lsyscache.h"
+#include "utils/typcache.h"
+
+
+/* declarations for dynamic loading */
+PG_FUNCTION_INFO_V1(isolate_tenant_to_new_shard);
+PG_FUNCTION_INFO_V1(worker_hash);
+
+
+/*
+ * isolate_tenant_to_new_shard isolates a tenant to its own shard by spliting
+ * the current matching shard.
+ */
+Datum
+isolate_tenant_to_new_shard(PG_FUNCTION_ARGS)
+{
+	ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					errmsg("isolate_tenant_to_new_shard() is only supported on "
+						   "Citus Enterprise")));
+}
+
+
+/*
+ * worker_hash returns the hashed value of the given value.
+ */
+Datum
+worker_hash(PG_FUNCTION_ARGS)
+{
+	Datum valueDatum = PG_GETARG_DATUM(0);
+	Datum hashedValueDatum = 0;
+	TypeCacheEntry *typeEntry = NULL;
+	FmgrInfo *hashFunction = NULL;
+	Oid valueDataType = InvalidOid;
+
+	/* figure out hash function from the data type */
+	valueDataType = get_fn_expr_argtype(fcinfo->flinfo, 0);
+	typeEntry = lookup_type_cache(valueDataType, TYPECACHE_HASH_PROC_FINFO);
+
+	if (typeEntry->hash_proc_finfo.fn_oid == InvalidOid)
+	{
+		ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+						errmsg("cannot find a hash function for the input type"),
+						errhint("Cast input to a data type with a hash function.")));
+	}
+
+	hashFunction = palloc0(sizeof(FmgrInfo));
+	fmgr_info_copy(hashFunction, &(typeEntry->hash_proc_finfo), CurrentMemoryContext);
+
+	/* calculate hash value */
+	hashedValueDatum = FunctionCall1(hashFunction, valueDatum);
+
+	PG_RETURN_INT32(hashedValueDatum);
+}

src/test/regress/expected/multi_extension.out

@@ -74,6 +74,7 @@ ALTER EXTENSION citus UPDATE TO '6.1-13';
 ALTER EXTENSION citus UPDATE TO '6.1-14';
 ALTER EXTENSION citus UPDATE TO '6.1-15';
 ALTER EXTENSION citus UPDATE TO '6.1-16';
+ALTER EXTENSION citus UPDATE TO '6.1-17';
 -- ensure no objects were created outside pg_catalog
 SELECT COUNT(*)
 FROM pg_depend AS pgd,

src/test/regress/expected/multi_utilities.out

@@ -319,6 +319,29 @@ VACUUM dustbunnies;
 WARNING:  not propagating VACUUM command to worker nodes
 HINT:  Set citus.enable_ddl_propagation to true in order to send targeted VACUUM commands to worker nodes.
 SET citus.enable_ddl_propagation to DEFAULT;
+-- test worker_hash
+SELECT worker_hash(123);
+ worker_hash 
+-------------
+  -205084363
+(1 row)
+
+SELECT worker_hash('1997-08-08'::date);
+ worker_hash 
+-------------
+  -499701663
+(1 row)
+
+-- test a custom type (this test should run after multi_data_types)
+SELECT worker_hash('(1, 2)');
+ERROR:  cannot find a hash function for the input type
+HINT:  Cast input to a data type with a hash function.
+SELECT worker_hash('(1, 2)'::test_composite_type);
+ worker_hash 
+-------------
+ -1895345704
+(1 row)
+
 -- TODO: support VERBOSE
 -- VACUUM VERBOSE dustbunnies;
 -- VACUUM (FULL, VERBOSE) dustbunnies;

src/test/regress/multi_schedule

@@ -135,9 +135,9 @@ test: multi_repair_shards
 test: multi_modifications
 test: multi_upsert
 test: multi_simple_queries
-test: multi_utilities
 test: multi_create_insert_proxy
 test: multi_data_types
+test: multi_utilities
 test: multi_repartition_udt
 test: multi_repartitioned_subquery_udf
 test: multi_modifying_xacts

src/test/regress/multi_task_tracker_extra_schedule

@@ -90,9 +90,9 @@ test: multi_repair_shards
 test: multi_modifications
 test: multi_upsert
 test: multi_simple_queries
-test: multi_utilities
 test: multi_create_insert_proxy
 test: multi_data_types
+test: multi_utilities
 
 # ---------
 # multi_copy creates hash and range-partitioned tables and performs COPY

src/test/regress/sql/multi_extension.sql

@@ -74,6 +74,7 @@ ALTER EXTENSION citus UPDATE TO '6.1-13';
 ALTER EXTENSION citus UPDATE TO '6.1-14';
 ALTER EXTENSION citus UPDATE TO '6.1-15';
 ALTER EXTENSION citus UPDATE TO '6.1-16';
+ALTER EXTENSION citus UPDATE TO '6.1-17';
 
 -- ensure no objects were created outside pg_catalog
 SELECT COUNT(*)

src/test/regress/sql/multi_utilities.sql

@@ -209,6 +209,14 @@ SET citus.enable_ddl_propagation to false;
 VACUUM dustbunnies;
 SET citus.enable_ddl_propagation to DEFAULT;
 
+-- test worker_hash
+SELECT worker_hash(123);
+SELECT worker_hash('1997-08-08'::date);
+
+-- test a custom type (this test should run after multi_data_types)
+SELECT worker_hash('(1, 2)');
+SELECT worker_hash('(1, 2)'::test_composite_type);
+
 -- TODO: support VERBOSE
 -- VACUUM VERBOSE dustbunnies;
 -- VACUUM (FULL, VERBOSE) dustbunnies;