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29 lines
760 B
SQL
29 lines
760 B
SQL
--
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-- RANDOM
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-- Test the random function
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--
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-- count the number of tuples originally
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SELECT count(*) FROM onek;
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-- select roughly 1/10 of the tuples
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-- Assume that the "onek" table has 1000 tuples
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-- and try to bracket the correct number so we
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-- have a regression test which can pass/fail
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-- - thomas 1998-08-17
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SELECT count(*) AS random INTO RANDOM_TBL
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FROM onek WHERE oidrand(onek.oid, 10);
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-- select again, the count should be different
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INSERT INTO RANDOM_TBL (random)
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SELECT count(*)
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FROM onek WHERE oidrand(onek.oid, 10);
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-- now test the results for randomness in the correct range
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SELECT random, count(random) FROM RANDOM_TBL
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GROUP BY random HAVING count(random) > 1;
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SELECT random FROM RANDOM_TBL
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WHERE random NOT BETWEEN 80 AND 120;
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