CREATE TABLE t1 ( uid INTEGER PRIMARY KEY, uname TEXT NOT NULL );
CREATE TABLE
INSERT INTO t1 VALUES ( 101, 'Park Gyu-Ri' );
INSERT 0 1
INSERT INTO t1 VALUES ( 102, 'Han Seung-Yeon' );
INSERT 0 1
INSERT INTO t1 VALUES ( 103, 'Nicole' );
INSERT 0 1
INSERT INTO t1 VALUES ( 104, 'Koo Ha-Ra' );
INSERT 0 1
INSERT INTO t1 VALUES ( 105, 'Kang Ji-Young' );
INSERT 0 1
ANALYZE t1;
ANALYZE
SELECT pgperf.create_snapshot_pg_stats(0);
 create_snapshot_pg_stats 
--------------------------
 t
(1 row)

SELECT count(*) FROM pgperf.snapshot_pg_stats WHERE schemaname = 'public';
 count 
-------
     2
(1 row)

SELECT pgperf.create_snapshot_pg_stats(1);
 create_snapshot_pg_stats 
--------------------------
 t
(1 row)

SELECT count(*) FROM pgperf.snapshot_pg_stats WHERE schemaname = 'public';
 count 
-------
     4
(1 row)

SELECT pgperf.create_snapshot_pg_stats(2);
 create_snapshot_pg_stats 
--------------------------
 t
(1 row)

SELECT count(*) FROM pgperf.snapshot_pg_stats WHERE schemaname = 'public';
 count 
-------
     6
(1 row)

SELECT pgperf.delete_snapshot_pg_stats(1);
 delete_snapshot_pg_stats 
--------------------------
 t
(1 row)

SELECT count(*) FROM pgperf.snapshot_pg_stats WHERE schemaname = 'public';
 count 
-------
     4
(1 row)

SELECT pgperf.delete_snapshot_pg_stats(0);
 delete_snapshot_pg_stats 
--------------------------
 t
(1 row)

SELECT count(*) FROM pgperf.snapshot_pg_stats WHERE schemaname = 'public';
 count 
-------
     2
(1 row)

SELECT pgperf.delete_snapshot_pg_stats(2);
 delete_snapshot_pg_stats 
--------------------------
 t
(1 row)

SELECT count(*) FROM pgperf.snapshot_pg_stats WHERE schemaname = 'public';
 count 
-------
     0
(1 row)

DROP TABLE t1;
DROP TABLE