QUERY: PURGE hash_f8_heap BEFORE 'now';
QUERY: SELECT count(*) AS has_10002 FROM hash_f8_heap[,] h;
has_10002
---------
    10002
(1 row)

QUERY: VACUUM hash_f8_heap;
QUERY: SELECT count(*) AS has_10000 FROM hash_f8_heap[,] h;
has_10000
---------
    10000
(1 row)

QUERY: PURGE hash_i4_heap AFTER '@ 1 second ago';
QUERY: SELECT count(*) AS has_10002 FROM hash_i4_heap[,] h;
has_10002
---------
    10002
(1 row)

QUERY: VACUUM hash_i4_heap;
QUERY: SELECT count(*) AS has_10000 FROM hash_i4_heap[,] h;
has_10000
---------
    10000
(1 row)