?? random.out
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---- RANDOM-- Test the random function---- count the number of tuples originallySELECT count(*) FROM onek; count ------- 1000(1 row)-- select roughly 1/10 of the tuples-- Assume that the "onek" table has 1000 tuples-- and try to bracket the correct number so we-- have a regression test which can pass/fail-- - thomas 1998-08-17SELECT count(*) AS random INTO RANDOM_TBL FROM onek WHERE random() < 1.0/10;-- select again, the count should be differentINSERT INTO RANDOM_TBL (random) SELECT count(*) FROM onek WHERE random() < 1.0/10;-- now test the results for randomness in the correct rangeSELECT random, count(random) FROM RANDOM_TBL GROUP BY random HAVING count(random) > 1; random | count --------+-------(0 rows)SELECT random FROM RANDOM_TBL WHERE random NOT BETWEEN 80 AND 120; random --------(0 rows)
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