Parsed test spec with 2 sessions

starting permutation: r_begin r_read1 w_delete_all w_compact r_read2 r_commit
step r_begin: BEGIN ISOLATION LEVEL REPEATABLE READ;
step r_read1: SELECT count(*) FROM iso;
count
-----
   50
(1 row)

step w_delete_all: DELETE FROM iso;
step w_compact: SELECT pgcolumnar.compact('iso');
compact
-------
      0
(1 row)

step r_read2: SELECT count(*) FROM iso;
count
-----
   50
(1 row)

step r_commit: COMMIT;