The following script can be used to create the two tables T1000 and T000000 with 1,000 and 1,000,000 records in respectively.
CREATE TABLE t1000
AS
SELECT rownum AS num
FROM dual
CONNECT BY rownum <= 1000;
CREATE TABLE t1000000 COMPRESS
AS
SELECT rownum AS num
FROM t1000, t1000;
-- Note the following block calling DBMS_STATS.gather_table_stats is not necessary from Oracle 12.1 onwards
BEGIN
DBMS_STATS.gather_table_stats(user, 't1000');
DBMS_STATS.gather_table_stats(user, 't1000000');
END;
/
COLUMN table_name FORMAT a30
SELECT table_name, num_rows, blocks, compression
FROM tabs
WHERE table_name IN ('T1000', 'T1000000');