72bd38cc99
Replace (expr op C1) OR (expr op C2) ... with expr op ANY(ARRAY[C1, C2, ...]) on the preliminary stage of optimization when we are still working with the expression tree. Here Cn is a n-th constant expression, 'expr' is non-constant expression, 'op' is an operator which returns boolean result and has a commuter (for the case of reverse order of constant and non-constant parts of the expression, like 'Cn op expr'). Sometimes it can lead to not optimal plan. This is why there is a or_to_any_transform_limit GUC. It specifies a threshold value of length of arguments in an OR expression that triggers the OR-to-ANY transformation. Generally, more groupable OR arguments mean that transformation will be more likely to win than to lose. Discussion: https://postgr.es/m/567ED6CA.2040504%40sigaev.ru Author: Alena Rybakina <lena.ribackina@yandex.ru> Author: Andrey Lepikhov <a.lepikhov@postgrespro.ru> Reviewed-by: Peter Geoghegan <pg@bowt.ie> Reviewed-by: Ranier Vilela <ranier.vf@gmail.com> Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com> Reviewed-by: Robert Haas <robertmhaas@gmail.com> Reviewed-by: Jian He <jian.universality@gmail.com> |
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