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Re: WIP: collect frequency statistics for arrays - Mailing list pgsql-hackers

From Alexander Korotkov
Subject Re: WIP: collect frequency statistics for arrays
Date
Msg-id BANLkTi=JXWJehNq3Fd1XDUWm4f79_0r8Sg@mail.gmail.com
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In response to WIP: collect frequency statistics for arrays  (Alexander Korotkov <aekorotkov@gmail.com>)
Responses Re: WIP: collect frequency statistics for arrays  (Alexander Korotkov <aekorotkov@gmail.com>)
Re: WIP: collect frequency statistics for arrays  (Simon Riggs <simon@2ndQuadrant.com>)
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Second version of patch attached. Main changes:
1) ANY and ALL keywords handling.
2) Collecting statistics of array length. It is used in "column <@ const".
3) Relatively accurate estimation of "column <@ const" selectivity. This estimation is most hard part of patch. I'm warrying that there could be too expensibe calculations for estimation. Also, likely current comments don't clearify anything...

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With best regards,
Alexander Korotkov.
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