Commit Graph

2 Commits

Author SHA1 Message Date
proller
c1904d3c55
Build and test fixes (#2470) 2018-06-05 20:43:10 +03:00
Alex Bocharov
9963e2f160 Fix uniqHLL12 and uniqCombined for cardinalities 100M+.
* Changing size() return type from UInt32 to UInt64 to prevent overflow (this shouldn't break back compatibility).
 * Removing "big cardinalities fix" for cardinalities >2^32/30 as it was very inaccurate and for estimates >2^32 it was trying to do 'log' of negative number which is NaN and it was casted to 0.
 * Adding python script to show that intHash32 is not a good choice for HyperLogLog algorithm when it's used for linear counting branch of it.
 * Adding bash script to test uniq, uniqHLL12, uniqCombined on different set cardinalities.
 * Altering documentation of uniq* aggregate functions with recommendations to use uniq instead of uniqHLL12 or uniqCombined.
2018-01-31 11:36:01 +00:00