читаемость запроса лучше

Misha v.3 17.05.2006 16:49 / 17.05.2006 17:09

в плане производительности думаю оптимизаторы сами это заменяют, хотя я не проверял.

http://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html

expr IN (value,...)

Returns 1 if expr is equal to any of the values in the IN list, else returns 0. If all values are constants, they are evaluated according to the type of expr and sorted. The search for the item then is done using a binary search. This means IN is very quick if the IN value list consists entirely of constants.

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