MySQL use query cache cache Simple Tutorial

1. Query cache key is a SQL string, and requires exact matching: The case is not the same or more than one space, will result in cache miss

2. Query cache directly the user input of the original SQL as a key, not to parse or optimized after the SQL as a key, also will not be a subquery in which the independent cache

2. SQL results in stored procedures are not cached

3. If a SQL produces an indeterminate result (even if the data in the table is not changed), such as Select Now (), MySQL will not cache its results

4. Any changes in the data in the table will result in all query cache related to this table being invalidated