Postgresql function to create partition table by city_id

create_city_partition.sql

CREATE OR REPLACE FUNCTION create_city_partition(schema_name text, parent_table_name text, city_id int)
  RETURNS text AS
$func$
DECLARE
	partition_table_name text;
BEGIN
	partition_table_name := parent_table_name || '_' || city_id::text;
EXECUTE format('
   CREATE TABLE %I.%I PARTITION OF %I FOR VALUES IN (%L)
   ', schema_name, partition_table_name, parent_table_name, city_id);
RETURN schema_name || '.' || partition_table_name;
END
$func$ LANGUAGE plpgsql;