GitHub user DaveBirdsall opened a pull request:
https://github.com/apache/trafodion/pull/1450
[TRAFODION-2964] Fix bug in new MDAM costing code concerning comparisons
This change fixes a bug in the new MDAM costing code. The code checks for a
mix of less than and greater than predicates and if so detected uses the square
of the HIST_DEFAULT_SEL_FOR_PRED_RANGE when calculating the UEC for the range.
But the code was assuming the key column was always on the left. It turns out
this assumption is not true. With this change, we no longer make this
assumption but instead check to see which side of the comparison operator has
the key column.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/DaveBirdsall/trafodion Trafodion2964
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/trafodion/pull/1450.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #1450
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commit 55211ac16c395a6e65205ec4f50fcce6b6fef28b
Author: Dave Birdsall <dbirdsall@...>
Date: 2018-02-20T18:34:40Z
[TRAFODION-2964] Fix bug in new MDAM costing code concerning comparisons
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