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4feb4f3a54
Currently implementation of rand/random built-in functions use rand_r of C library. We recognized its randomness was poor. pcg32 of third party library shows better randomness than rand_r. Testing: Revise unit test in expr-test Add E2E test to random.test Change-Id: Idafdd5fe7502ff242c76a91a815c565146108684 Reviewed-on: http://gerrit.cloudera.org:8080/8355 Reviewed-by: Jim Apple <jbapple-impala@apache.org> Tested-by: Impala Public Jenkins
25 lines
549 B
Plaintext
25 lines
549 B
Plaintext
# These computations take a while so we do not want to add too many test cases
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# They also require a non-trivial amount of data to get reasonable results.
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====
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---- QUERY
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select count(distinct rand()), count(*) from alltypes a;
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---- TYPES
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bigint, bigint
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---- RESULTS
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7300,7300
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====
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---- QUERY
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select count(distinct rand(100)), count(*) from alltypes a;
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---- TYPES
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bigint, bigint
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---- RESULTS
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7300,7300
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====
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---- QUERY
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select count(distinct rand()), count(*) from alltypes a, alltypes b;
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---- TYPES
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bigint, bigint
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---- RESULTS
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53290000,53290000
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====
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