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MySQL provides a mechanism to cache a query and its result set for reuse by all users. This can be extremely effective in environments where a large number of small, lexically equivalent queries are repeated often. Parameters Affecting the Query Cache Parameters in the my.cnf file exist to enable, configure and tune the query cache. Pay careful attention to the values of query_cache_size and query_cache_type because they interact in a non-standard way and can cause confusion.