--
-- Test different operations on empty columnar tables.
--
SET citus.compression to 'none';
create table t_uncompressed(a int) using columnar;
create table t_compressed(a int) using columnar;
-- set options
SELECT alter_columnar_table_set('t_compressed', compression => 'pglz');
 alter_columnar_table_set
---------------------------------------------------------------------

(1 row)

SELECT alter_columnar_table_set('t_compressed', stripe_row_count => 100);
 alter_columnar_table_set
---------------------------------------------------------------------

(1 row)

SELECT alter_columnar_table_set('t_compressed', chunk_row_count => 100);
 alter_columnar_table_set
---------------------------------------------------------------------

(1 row)

SELECT * FROM columnar.options WHERE regclass = 't_compressed'::regclass;
   regclass   | chunk_row_count | stripe_row_count | compression_level | compression
---------------------------------------------------------------------
 t_compressed |             100 |              100 |                 3 | pglz
(1 row)

-- select
select * from t_uncompressed;
 a
---------------------------------------------------------------------
(0 rows)

select count(*) from t_uncompressed;
 count
---------------------------------------------------------------------
     0
(1 row)

select * from t_compressed;
 a
---------------------------------------------------------------------
(0 rows)

select count(*) from t_compressed;
 count
---------------------------------------------------------------------
     0
(1 row)

-- explain
explain (costs off, summary off, timing off) select * from t_uncompressed;
                  QUERY PLAN
---------------------------------------------------------------------
 Custom Scan (ColumnarScan) on t_uncompressed
(1 row)

explain (costs off, summary off, timing off) select * from t_compressed;
                 QUERY PLAN
---------------------------------------------------------------------
 Custom Scan (ColumnarScan) on t_compressed
(1 row)

-- vacuum
vacuum verbose t_compressed;
INFO:  statistics for "t_compressed":
storage id: -1
total file size: 0, total data size: 0
compression rate: 1.00x
total row count: 0, stripe count: 0, average rows per stripe: 0
chunk count: 0, containing data for dropped columns: 0

vacuum verbose t_uncompressed;
INFO:  statistics for "t_uncompressed":
storage id: -1
total file size: 0, total data size: 0
compression rate: 1.00x
total row count: 0, stripe count: 0, average rows per stripe: 0
chunk count: 0, containing data for dropped columns: 0

-- vacuum full
vacuum full t_compressed;
vacuum full t_uncompressed;
-- analyze
analyze t_uncompressed;
analyze t_compressed;
-- truncate
truncate t_uncompressed;
truncate t_compressed;
-- alter type
alter table t_uncompressed alter column a type text;
alter table t_compressed alter column a type text;
-- drop
drop table t_compressed;
drop table t_uncompressed;