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$ gg -e 'numbers(toUInt64' -e 'numbers_mt(toUInt64' | cut -d: -f1 | sort -u | xargs sed -i -E 's#numbers(_mt|)\(toUInt64\(([^()]*)\)\)#numbers\1(\2)#'
10 lines
398 B
SQL
10 lines
398 B
SQL
-- for small cardinality the 64 bit hash perform worse, but for 1e10:
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-- 4 byte hash: 2.8832809652e10
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-- 8 byte hash: 0.9998568925e10
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-- but hence checking with 1e10 values takes too much time (~45 secs), this
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-- test is just to ensure that the result is different (and to document the
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-- outcome).
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SELECT uniqCombined(number) FROM numbers(1e7);
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SELECT uniqCombined64(number) FROM numbers(1e7);
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