opt: set join reorder limit to 4 by default #34549
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Release note (sql change): The cost-based optimizer will now reorder up to 4 joins by default to attempt to find a better ordering of them. This behaviour can be disabled per-session by setting the `experimental_reorder_joins_limit` session variable to 0.
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andy-kimball
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Feb 5, 2019
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complete! 1 of 0 LGTMs obtained (waiting on @andy-kimball, @RaduBerinde, and @rytaft)
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34549: opt: set join reorder limit to 4 by default r=andy-kimball a=justinj Release note (sql change): The cost-based optimizer will now reorder up to 4 joins by default to attempt to find a better ordering of them. This behaviour can be disabled per-session by setting the `experimental_reorder_joins_limit` session variable to 0. Co-authored-by: Justin Jaffray <justin@cockroachlabs.com>
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Release note (sql change): The cost-based optimizer will now reorder up
to 4 joins by default to attempt to find a better ordering of them. This
behaviour can be disabled per-session by setting the
experimental_reorder_joins_limitsession variable to 0.