Optimizing the MySQL IN() Comparison Operations Which Include the Indexed Field - MySQL DiaryThe MySQL IN() Comparison Operator is said to be very quick if all the values are constants (the values are then evaluated and sorted first, and the search is done using a binary search). However, what if the field which the IN clause refers to, is part of the index used to execute the query? For example, lets create a table t with columns a to e Create table t ( a int unsigned NOT NULL, b int uns
