This is a repository of useful MySQL Proxy scripts targetting mainly developers in quest of debugging.

MySQL Proxy >= 0.8 (May work with earlier version, untested)

$ mysql-proxy --proxy-lua-script=/absolute/path/to/the/script.lua

Prints every SQL command received while cleaning obsolete spaces. Every command appears on one line with the following additional information:

• an optional informative message about the query,
• the number of rows returned or affected by the query,
• the amout of time (in ms) it took to run the query.

Additionally, colors are used to provide direct information on the queries:

• yellow: when not using a good index (no_good_index_used flag),
• yellow + bold: when not using an index at all,
• red: when an error occured,
• pink: for queries affecting records.

Colors are also used to denote slow queries: time displayed in red instead of green. When a query returns no rows nor affect records, "" is displayed using red in reverse video.

If you want to force "SQL_NO_CACHE" in your SELECT statements you can set the use_sql_no_cache variable to 1.

Same as debug.lua, but without shell colors.

Same as debug.lua, but logs to a file (/var/log/mysql-proxy/querydebug.log) and with different fields.

Simulates a server being slow because of huge traffic.

The sleep command accepting a float as argument is required to make this script works out of the box.

The slowdowns can be configured to make all requests longer by a factor or by a fixed amount of time (or both).

By default, requests are made twice slower with an additional overhead of 0.1s.