Menu
With the FLUSH QUERY CACHE command you can defragment the query cache to better utilise its memory. This command will not remove any queries from the cache. FLUSH TABLES also flushes the query cache. The RESET QUERY CACHE command removes all query results from the query cache.
To clear SQL Server's cache, run DBCC DROPCLEANBUFFERS , which clears all data from the cache. Then run DBCC FREEPROCCACHE , which clears the stored procedure cache.
MySQL determines the queries to cache by examining the query_cache_type variable. Setting this value to 0 or OFF prevents caching or retrieval of cached queries. You can also set it to 1 to enable caching for all queries except for ones beginning with the SELECT SQL_NO_CACHE statement.
Query to disable the cache From the MySQL command line, a application like phpMyAdmin, or from a script, run the following SQL command to disable the query cache: SET GLOBAL query_cache_size = 0; This will take effect immediately. You will also need to modify the MySQL configuration file to keep it disabled on reboot.
I believe you can use...
RESET QUERY CACHE;
...if the user you're running as has reload rights. Alternatively, you can defragment the query cache via...
FLUSH QUERY CACHE;
See the Query Cache Status and Maintenance section of the MySQL manual for more information.
In my system (Ubuntu 12.04) I found RESET QUERY CACHE and even restarting mysql server not enough. This was due to memory disc caching.
After each query, I clean the disc cache in the terminal:
sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
and then reset the query cache in mysql client:
RESET QUERY CACHE;
according the documentation, this should do it...
RESET QUERY CACHE
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With