Make columnar as independent citus_columnar extension

src/backend/columnar/Makefile

@@ -8,10 +8,17 @@ OBJS += \
 	$(patsubst $(citus_abs_srcdir)/%.c,%.o,$(foreach dir,$(SUBDIRS), $(sort $(wildcard $(citus_abs_srcdir)/$(dir)/*.c))))
 
 MODULE_big = citus_columnar
-
+EXTENSION = citus_columnar
+DATA = $(wildcard sql/*--*.sql)
 PG_CPPFLAGS += -I$(libpq_srcdir) -I$(safestringlib_srcdir)/include
 
+ifdef USE_PGXS
+PG_CONFIG = pg_config
+PGXS := $(shell $(PG_CONFIG) --pgxs)
+include $(PGXS)
+else
 include $(citus_top_builddir)/Makefile.global
 
 .PHONY: install-all
 install-all: install
+endif

src/backend/columnar/citus_columnar.control

@@ -0,0 +1,6 @@
+# Columnar extension
+comment = 'Citus Columnar extension'
+default_version = '11.0-2'
+module_pathname = '$libdir/citus_columnar'
+relocatable = false
+schema = pg_catalog 

src/backend/columnar/sql/citus_columnar--11.0-2.sql

@@ -0,0 +1,338 @@
+-- columnar--9.5-1--10.0-1.sql
+
+CREATE SCHEMA IF NOT EXISTS columnar;
+SET search_path TO columnar;
+
+
+CREATE SEQUENCE IF NOT EXISTS storageid_seq MINVALUE 10000000000 NO CYCLE;
+
+CREATE TABLE IF NOT EXISTS options (
+    regclass regclass NOT NULL PRIMARY KEY,
+    chunk_group_row_limit int NOT NULL,
+    stripe_row_limit int NOT NULL,
+    compression_level int NOT NULL,
+    compression name NOT NULL
+) WITH (user_catalog_table = true);
+
+COMMENT ON TABLE options IS 'columnar table specific options, maintained by alter_columnar_table_set';
+
+CREATE TABLE IF NOT EXISTS stripe (
+    storage_id bigint NOT NULL,
+    stripe_num bigint NOT NULL,
+    file_offset bigint NOT NULL,
+    data_length bigint NOT NULL,
+    column_count int NOT NULL,
+    chunk_row_count int NOT NULL,
+    row_count bigint NOT NULL,
+    chunk_group_count int NOT NULL,
+    PRIMARY KEY (storage_id, stripe_num)
+) WITH (user_catalog_table = true);
+
+COMMENT ON TABLE stripe IS 'Columnar per stripe metadata';
+
+CREATE TABLE IF NOT EXISTS chunk_group (
+    storage_id bigint NOT NULL,
+    stripe_num bigint NOT NULL,
+    chunk_group_num int NOT NULL,
+    row_count bigint NOT NULL,
+    PRIMARY KEY (storage_id, stripe_num, chunk_group_num),
+    FOREIGN KEY (storage_id, stripe_num) REFERENCES stripe(storage_id, stripe_num) ON DELETE CASCADE
+);
+
+COMMENT ON TABLE chunk_group IS 'Columnar chunk group metadata';
+
+CREATE TABLE IF NOT EXISTS chunk (
+    storage_id bigint NOT NULL,
+    stripe_num bigint NOT NULL,
+    attr_num int NOT NULL,
+    chunk_group_num int NOT NULL,
+    minimum_value bytea,
+    maximum_value bytea,
+    value_stream_offset bigint NOT NULL,
+    value_stream_length bigint NOT NULL,
+    exists_stream_offset bigint NOT NULL,
+    exists_stream_length bigint NOT NULL,
+    value_compression_type int NOT NULL,
+    value_compression_level int NOT NULL,
+    value_decompressed_length bigint NOT NULL,
+    value_count bigint NOT NULL,
+    PRIMARY KEY (storage_id, stripe_num, attr_num, chunk_group_num),
+    FOREIGN KEY (storage_id, stripe_num, chunk_group_num) REFERENCES chunk_group(storage_id, stripe_num, chunk_group_num) ON DELETE CASCADE
+) WITH (user_catalog_table = true);
+
+COMMENT ON TABLE chunk IS 'Columnar per chunk metadata';
+
+DO $proc$
+BEGIN
+
+-- from version 12 and up we have support for tableam's if installed on pg11 we can't
+-- create the objects here. Instead we rely on citus_finish_pg_upgrade to be called by the
+-- user instead to add the missing objects
+IF substring(current_Setting('server_version'), '\d+')::int >= 12 THEN
+  EXECUTE $$
+--#include "udfs/columnar_handler/10.0-1.sql"
+CREATE OR REPLACE FUNCTION columnar.columnar_handler(internal)
+    RETURNS table_am_handler
+    LANGUAGE C
+AS 'MODULE_PATHNAME', 'columnar_handler';
+COMMENT ON FUNCTION columnar.columnar_handler(internal)
+    IS 'internal function returning the handler for columnar tables';
+
+-- postgres 11.8 does not support the syntax for table am, also it is seemingly trying
+-- to parse the upgrade file and erroring on unknown syntax.
+-- normally this section would not execute on postgres 11 anyway. To trick it to pass on
+-- 11.8 we wrap the statement in a plpgsql block together with an EXECUTE. This is valid
+-- syntax on 11.8 and will execute correctly in 12
+DO $create_table_am$
+BEGIN
+  EXECUTE 'CREATE ACCESS METHOD columnar TYPE TABLE HANDLER columnar.columnar_handler';
+END $create_table_am$;
+
+--#include "udfs/alter_columnar_table_set/10.0-1.sql"
+CREATE OR REPLACE FUNCTION pg_catalog.alter_columnar_table_set(
+    table_name regclass,
+    chunk_group_row_limit int DEFAULT NULL,
+    stripe_row_limit int DEFAULT NULL,
+    compression name DEFAULT null,
+    compression_level int DEFAULT NULL)
+    RETURNS void
+    LANGUAGE C
+AS 'MODULE_PATHNAME', 'alter_columnar_table_set';
+
+COMMENT ON FUNCTION pg_catalog.alter_columnar_table_set(
+    table_name regclass,
+    chunk_group_row_limit int,
+    stripe_row_limit int,
+    compression name,
+    compression_level int)
+IS 'set one or more options on a columnar table, when set to NULL no change is made';
+
+
+--#include "udfs/alter_columnar_table_reset/10.0-1.sql"
+CREATE OR REPLACE FUNCTION pg_catalog.alter_columnar_table_reset(
+    table_name regclass,
+    chunk_group_row_limit bool DEFAULT false,
+    stripe_row_limit bool DEFAULT false,
+    compression bool DEFAULT false,
+    compression_level bool DEFAULT false)
+    RETURNS void
+    LANGUAGE C
+AS 'MODULE_PATHNAME', 'alter_columnar_table_reset';
+
+COMMENT ON FUNCTION pg_catalog.alter_columnar_table_reset(
+    table_name regclass,
+    chunk_group_row_limit bool,
+    stripe_row_limit bool,
+    compression bool,
+    compression_level bool)
+IS 'reset on or more options on a columnar table to the system defaults';
+
+  $$;
+END IF;
+END$proc$;
+
+-- add citus_internal schema
+CREATE SCHEMA IF NOT EXISTS citus_internal;
+
+-- (this function being dropped in 10.0.3)->#include "udfs/columnar_ensure_objects_exist/10.0-1.sql"
+
+-- citus_internal.columnar_ensure_objects_exist is an internal helper function to create
+-- missing objects, anything related to the table access methods.
+-- Since the API for table access methods is only available in PG12 we can't create these
+-- objects when Citus is installed in PG11. Once citus is installed on PG11 the user can
+-- upgrade their database to PG12. Now they require the table access method objects that
+-- we couldn't create before.
+-- This internal function is called from `citus_finish_pg_upgrade` which the user is
+-- required to call after a PG major upgrade.
+-- CREATE OR REPLACE FUNCTION citus_internal.columnar_ensure_objects_exist()
+--     RETURNS void
+--     LANGUAGE plpgsql
+--     SET search_path = pg_catalog
+-- AS $ceoe$
+-- BEGIN
+
+-- when postgres is version 12 or above we need to create the tableam. If the tableam
+-- exist we assume all objects have been created.
+-- IF substring(current_Setting('server_version'), '\d+')::int >= 12 THEN
+-- IF NOT EXISTS (SELECT 1 FROM pg_am WHERE amname = 'columnar') THEN
+
+-- --#include "../columnar_handler/10.0-1.sql"
+
+-- --#include "../alter_columnar_table_set/10.0-1.sql"
+
+-- --#include "../alter_columnar_table_reset/10.0-1.sql"
+
+--     -- add the missing objects to the extension
+--     ALTER EXTENSION citus ADD FUNCTION columnar.columnar_handler(internal);
+--     ALTER EXTENSION citus ADD ACCESS METHOD columnar;
+--     ALTER EXTENSION citus ADD FUNCTION pg_catalog.alter_columnar_table_set(
+--         table_name regclass,
+--         chunk_group_row_limit int,
+--         stripe_row_limit int,
+--         compression name,
+--         compression_level int);
+--     ALTER EXTENSION citus ADD FUNCTION pg_catalog.alter_columnar_table_reset(
+--         table_name regclass,
+--         chunk_group_row_limit bool,
+--         stripe_row_limit bool,
+--         compression bool,
+--         compression_level bool);
+
+-- END IF;
+-- END IF;
+-- END;
+-- $ceoe$;
+
+--COMMENT ON FUNCTION citus_internal.columnar_ensure_objects_exist()
+--     IS 'internal function to be called by pg_catalog.citus_finish_pg_upgrade responsible for creating the columnar objects';
+
+
+RESET search_path;
+
+-- columnar--10.0.-1 --10.0.2
+GRANT USAGE ON SCHEMA columnar TO PUBLIC;
+GRANT SELECT ON ALL tables IN SCHEMA columnar TO PUBLIC ;
+
+-- columnar--10.0-3--10.1-1.sql
+
+-- Drop foreign keys between columnar metadata tables.
+-- Postgres assigns different names to those foreign keys in PG11, so act accordingly.
+DO $proc$
+BEGIN
+IF substring(current_Setting('server_version'), '\d+')::int >= 12 THEN
+  EXECUTE $$
+ALTER TABLE columnar.chunk DROP CONSTRAINT chunk_storage_id_stripe_num_chunk_group_num_fkey;
+ALTER TABLE columnar.chunk_group DROP CONSTRAINT chunk_group_storage_id_stripe_num_fkey;
+  $$;
+ELSE
+  EXECUTE $$
+ALTER TABLE columnar.chunk DROP CONSTRAINT chunk_storage_id_fkey;
+ALTER TABLE columnar.chunk_group DROP CONSTRAINT chunk_group_storage_id_fkey;
+  $$;
+END IF;
+END$proc$;
+
+-- since we dropped pg11 support, we don't need to worry about missing
+-- columnar objects when upgrading postgres
+-- DROP FUNCTION citus_internal.columnar_ensure_objects_exist();
+
+--10.1-1 -- 10.2-1
+
+-- columnar--10.1-1--10.2-1.sql
+
+-- For a proper mapping between tid & (stripe, row_num), add a new column to
+-- columnar.stripe and define a BTREE index on this column.
+-- Also include storage_id column for per-relation scans.
+ALTER TABLE columnar.stripe ADD COLUMN first_row_number bigint;
+CREATE INDEX stripe_first_row_number_idx ON columnar.stripe USING BTREE(storage_id, first_row_number);
+
+-- Populate first_row_number column of columnar.stripe table.
+--
+-- For simplicity, we calculate MAX(row_count) value across all the stripes
+-- of all the columanar tables and then use it to populate first_row_number
+-- column. This would introduce some gaps however we are okay with that since
+-- it's already the case with regular INSERT/COPY's.
+DO $$
+DECLARE
+  max_row_count bigint;
+  -- this should be equal to columnar_storage.h/COLUMNAR_FIRST_ROW_NUMBER
+  COLUMNAR_FIRST_ROW_NUMBER constant bigint := 1;
+BEGIN
+  SELECT MAX(row_count) INTO max_row_count FROM columnar.stripe;
+  UPDATE columnar.stripe SET first_row_number = COLUMNAR_FIRST_ROW_NUMBER +
+                                                (stripe_num - 1) * max_row_count;
+END;
+$$;
+
+--#include "udfs/upgrade_columnar_storage/10.2-1.sql"
+CREATE OR REPLACE FUNCTION citus_internal.upgrade_columnar_storage(rel regclass)
+  RETURNS VOID
+  STRICT
+  LANGUAGE c AS 'MODULE_PATHNAME', $$upgrade_columnar_storage$$;
+
+COMMENT ON FUNCTION citus_internal.upgrade_columnar_storage(regclass)
+  IS 'function to upgrade the columnar storage, if necessary';
+
+
+--#include "udfs/downgrade_columnar_storage/10.2-1.sql"
+
+CREATE OR REPLACE FUNCTION citus_internal.downgrade_columnar_storage(rel regclass)
+  RETURNS VOID
+  STRICT
+  LANGUAGE c AS 'MODULE_PATHNAME', $$downgrade_columnar_storage$$;
+
+COMMENT ON FUNCTION citus_internal.downgrade_columnar_storage(regclass)
+  IS 'function to downgrade the columnar storage, if necessary';
+
+-- upgrade storage for all columnar relations
+SELECT citus_internal.upgrade_columnar_storage(c.oid) FROM pg_class c, pg_am a
+  WHERE c.relam = a.oid AND amname = 'columnar';
+
+-- columnar--10.2-1--10.2-2.sql
+
+-- revoke read access for columnar.chunk from unprivileged
+-- user as it contains chunk min/max values
+REVOKE SELECT ON columnar.chunk FROM PUBLIC;
+
+
+-- columnar--10.2-2--10.2-3.sql
+
+-- Since stripe_first_row_number_idx is required to scan a columnar table, we
+-- need to make sure that it is created before doing anything with columnar
+-- tables during pg upgrades.
+--
+-- However, a plain btree index is not a dependency of a table, so pg_upgrade
+-- cannot guarantee that stripe_first_row_number_idx gets created when
+-- creating columnar.stripe, unless we make it a unique "constraint".
+--
+-- To do that, drop stripe_first_row_number_idx and create a unique
+-- constraint with the same name to keep the code change at minimum.
+DROP INDEX columnar.stripe_first_row_number_idx;
+ALTER TABLE columnar.stripe ADD CONSTRAINT stripe_first_row_number_idx
+UNIQUE (storage_id, first_row_number);
+
+-- columnar--10.2-3--10.2-4.sql
+
+CREATE OR REPLACE FUNCTION citus_internal.columnar_ensure_am_depends_catalog()
+  RETURNS void
+  LANGUAGE plpgsql
+  SET search_path = pg_catalog
+AS $func$
+BEGIN
+  INSERT INTO pg_depend
+  SELECT -- Define a dependency edge from "columnar table access method" ..
+         'pg_am'::regclass::oid as classid,
+         (select oid from pg_am where amname = 'columnar') as objid,
+         0 as objsubid,
+         -- ... to each object that is registered to pg_class and that lives
+         -- in "columnar" schema. That contains catalog tables, indexes
+         -- created on them and the sequences created in "columnar" schema.
+         --
+         -- Given the possibility of user might have created their own objects
+         -- in columnar schema, we explicitly specify list of objects that we
+         -- are interested in.
+         'pg_class'::regclass::oid as refclassid,
+         columnar_schema_members.relname::regclass::oid as refobjid,
+         0 as refobjsubid,
+         'n' as deptype
+  FROM (VALUES ('columnar.chunk'),
+               ('columnar.chunk_group'),
+               ('columnar.chunk_group_pkey'),
+               ('columnar.chunk_pkey'),
+               ('columnar.options'),
+               ('columnar.options_pkey'),
+               ('columnar.storageid_seq'),
+               ('columnar.stripe'),
+               ('columnar.stripe_first_row_number_idx'),
+               ('columnar.stripe_pkey')
+       ) columnar_schema_members(relname)
+  -- Avoid inserting duplicate entries into pg_depend.
+  EXCEPT TABLE pg_depend;
+END;
+$func$;
+COMMENT ON FUNCTION citus_internal.columnar_ensure_am_depends_catalog()
+  IS 'internal function responsible for creating dependencies from columnar '
+     'table access method to the rel objects in columnar schema';
+
+
+SELECT citus_internal.columnar_ensure_am_depends_catalog();

src/backend/columnar/sql/columnar--10.1-1--10.2-1.sql

@@ -28,5 +28,5 @@ $$;
 #include "udfs/downgrade_columnar_storage/10.2-1.sql"
 
 -- upgrade storage for all columnar relations
-SELECT citus_internal.upgrade_columnar_storage(c.oid) FROM pg_class c, pg_am a
+PERFORM citus_internal.upgrade_columnar_storage(c.oid) FROM pg_class c, pg_am a
   WHERE c.relam = a.oid AND amname = 'columnar';

src/backend/columnar/sql/columnar--10.2-3--10.2-4.sql

@@ -2,4 +2,4 @@
 
 #include "udfs/columnar_ensure_am_depends_catalog/10.2-4.sql"
 
-SELECT citus_internal.columnar_ensure_am_depends_catalog();
+PERFORM citus_internal.columnar_ensure_am_depends_catalog();

src/backend/distributed/Makefile

@@ -16,7 +16,7 @@ generated_sql_files = $(patsubst %,$(citus_abs_srcdir)/build/%,$(template_sql_fi
 generated_downgrade_sql_files += $(patsubst %,$(citus_abs_srcdir)/build/sql/%,$(template_downgrade_sql_files))
 # All citus--*.sql files that are used to upgrade between versions
 DATA_built = $(generated_sql_files)
-
+DATA = citus--11.0-2.control
 # directories with source files
 SUBDIRS = . commands connection ddl deparser executor metadata operations planner progress relay safeclib test transaction utils worker
 # enterprise modules

src/backend/distributed/citus--11.0-2.control

@@ -0,0 +1,4 @@
+# Citus extension 11.0-2
+relocatable = false
+schema = pg_catalog
+requires = 'citus_columnar'

src/backend/distributed/citus.control

@@ -1,6 +1,6 @@
 # Citus extension
 comment = 'Citus distributed database'
-default_version = '11.0-1'
+default_version = '11.0-2'
 module_pathname = '$libdir/citus'
 relocatable = false
 schema = pg_catalog

src/backend/distributed/sql/citus--10.0-1--10.0-2.sql

@@ -1,5 +1,12 @@
 -- citus--10.0-1--10.0-2
 
-#include "../../columnar/sql/columnar--10.0-1--10.0-2.sql"
+do $$ begin raise log 'citus--10.0-1--10.0-2.sql'; end; $$;
+DO $check_columnar$
+BEGIN
+  IF NOT EXISTS (select 1 from pg_extension where extname='citus_columnar') THEN  
+    #include "../../columnar/sql/columnar--10.0-1--10.0-2.sql"  
+  END IF;
+END;
+$check_columnar$;
 
 GRANT SELECT ON public.citus_tables TO public;

src/backend/distributed/sql/citus--10.0-4--10.1-1.sql

@@ -9,7 +9,14 @@ INSERT INTO citus.pg_dist_object SELECT
   0 as objsubid
 ON CONFLICT DO NOTHING;
 
-#include "../../columnar/sql/columnar--10.0-3--10.1-1.sql"
+DO $check_columnar$
+BEGIN
+  IF NOT EXISTS (select 1 from pg_extension where extname='citus_columnar') THEN  
+      #include "../../columnar/sql/columnar--10.0-3--10.1-1.sql"   
+  END IF;
+END;
+$check_columnar$;
+
 #include "udfs/create_distributed_table/10.1-1.sql";
 #include "udfs/worker_partitioned_relation_total_size/10.1-1.sql"
 #include "udfs/worker_partitioned_relation_size/10.1-1.sql"

src/backend/distributed/sql/citus--10.1-1--10.2-1.sql

@@ -9,7 +9,16 @@ GRANT ALL ON FUNCTION pg_catalog.worker_record_sequence_dependency(regclass,regc
 ALTER TABLE pg_catalog.pg_dist_placement ADD CONSTRAINT placement_shardid_groupid_unique_index UNIQUE (shardid, groupid);
 
 #include "udfs/stop_metadata_sync_to_node/10.2-1.sql"
-#include "../../columnar/sql/columnar--10.1-1--10.2-1.sql"
+
+DO $check_columnar$
+BEGIN
+  PERFORM 1 FROM pg_extension WHERE extname = 'citus_columnar';
+  IF NOT FOUND THEN  
+    #include "../../columnar/sql/columnar--10.1-1--10.2-1.sql"   
+  END IF;
+END;
+$check_columnar$;
+
 #include "udfs/citus_internal_add_partition_metadata/10.2-1.sql";
 #include "udfs/citus_internal_add_shard_metadata/10.2-1.sql";
 #include "udfs/citus_internal_add_placement_metadata/10.2-1.sql";

src/backend/distributed/sql/citus--10.2-1--10.2-2.sql

@@ -2,4 +2,10 @@
 
 -- bump version to 10.2-2
 
-#include "../../columnar/sql/columnar--10.2-1--10.2-2.sql"
+DO $check_columnar$
+BEGIN
+  IF NOT EXISTS (select 1 from pg_extension where extname='citus_columnar') THEN  
+    #include "../../columnar/sql/columnar--10.2-1--10.2-2.sql"  
+  END IF;
+END;
+$check_columnar$;

src/backend/distributed/sql/citus--10.2-2--10.2-3.sql

@@ -2,4 +2,10 @@
 
 -- bump version to 10.2-3
 
-#include "../../columnar/sql/columnar--10.2-2--10.2-3.sql"
+DO $check_columnar$
+BEGIN
+  IF NOT EXISTS (select 1 from pg_extension where extname='citus_columnar') THEN  
+    #include "../../columnar/sql/columnar--10.2-2--10.2-3.sql" 
+  END IF;
+END;
+$check_columnar$;

src/backend/distributed/sql/citus--10.2-3--10.2-4.sql

@@ -2,7 +2,14 @@
 
 -- bump version to 10.2-4
 
-#include "../../columnar/sql/columnar--10.2-3--10.2-4.sql"
+DO $check_columnar$
+BEGIN
+  PERFORM 1 FROM pg_extension WHERE extname = 'citus_columnar';
+  IF NOT FOUND THEN 
+    #include "../../columnar/sql/columnar--10.2-3--10.2-4.sql" 
+  END IF;
+END;
+$check_columnar$;
 
 #include "udfs/fix_partition_shard_index_names/10.2-4.sql"
 #include "udfs/fix_all_partition_shard_index_names/10.2-4.sql"

src/backend/distributed/sql/citus--11.0-1--11.0-2.sql

@@ -0,0 +1,4 @@
+-- bump up citus version
+-- citus--11.0-1--12.0-1.sql
+
+do $$ begin raise log 'citus--11.0-1--12.0-1'; end; $$;

src/backend/distributed/sql/citus--8.0-1.sql

@@ -1,6 +1,15 @@
 -- complain if script is sourced in psql, rather than via CREATE EXTENSION
 \echo Use "CREATE EXTENSION citus" to load this file. \quit
 
+DO $check_columnar$
+BEGIN
+  IF NOT EXISTS (select 1 from pg_extension where extname='citus_columnar') THEN  
+    RAISE EXCEPTION 'citus_columnar extension is missing'
+    USING HINT = 'Please install citus_columnar extension first';   
+  END IF;
+END;
+$check_columnar$;
+
 CREATE SCHEMA citus;
 
 SET search_path = 'pg_catalog';

src/backend/distributed/sql/citus--9.5-1--10.0-4.sql

@@ -35,7 +35,14 @@ DROP FUNCTION IF EXISTS pg_catalog.citus_total_relation_size(regclass);
 #include "udfs/worker_change_sequence_dependency/10.0-1.sql"
 #include "udfs/remove_local_tables_from_metadata/10.0-1.sql"
 
-#include "../../columnar/sql/columnar--9.5-1--10.0-1.sql"
+DO $check_columnar$
+BEGIN
+  IF NOT EXISTS (select 1 from pg_extension where extname='citus_columnar') THEN  
+    #include "../../columnar/sql/columnar--9.5-1--10.0-1.sql"   
+  END IF;
+END;
+$check_columnar$;
+
 
 #include "udfs/time_partition_range/10.0-1.sql"
 #include "udfs/time_partitions/10.0-1.sql"
@@ -172,7 +179,13 @@ GRANT SELECT ON pg_catalog.citus_worker_stat_activity TO PUBLIC;
 
 -- copy of citus--10.0-1--10.0-2
 
-#include "../../columnar/sql/columnar--10.0-1--10.0-2.sql"
+DO $check_columnar$
+BEGIN
+  IF NOT EXISTS (select 1 from pg_extension where extname='citus_columnar') THEN  
+    #include "../../columnar/sql/columnar--10.0-1--10.0-2.sql"   
+  END IF;
+END;
+$check_columnar$;
 
 -- copy of citus--10.0-2--10.0-3