New version of the selectivity estimation patch attached. I am adding it to CommitFest 2014-06. Previous version of it reviewed by Andreas Karlson on the previous CommitFest with the GiST support patch. The new version includes join selectivity estimation.
Join selectivity is calculated in 4 steps: * matching first MCV to second MCV * searching first MCV in the second histogram * searching second MCV in the first histogram * searching boundaries of the first histogram in the second histogram Comparing the lists with each other slows down the function when statistics set to higher values. To avoid this problem I only use log(n) values of the lists. It is the first log(n) value for MCV, evenly separated values for histograms. In my tests, this optimization does not affect the planning time when statistics = 100, but does affect accuracy of the estimation. I can send the version without this optimization, if slow down with larger statistics is not a problem which should be solved on the selectivity estimation function. I also attach the script I was using for testing and I left log statements in the networkjoinsel() function to make testing easier. These statements should be removed before commit.
inet-selfuncs-v4.patch
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inet-selfuncs-test.sql
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