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Per-query variable statement

Percona Server has implemented per-query variable statement support in 5.6.14-62.0. This feature provides the ability to set variable values only for a certain query, after execution of which the previous values will be restored. Per-query variable values can be set up with the following command:

mysql> SET STATEMENT <variable=value> FOR <statement>;

Examples

If we want to increase the sort_buffer_size value just for one specific sort query we can do it like this:

mysql> SET STATEMENT sort_buffer_size=100000 FOR SELECT name FROM name ORDER BY name;

This feature can also be used with Statement Timeout to limit the execution time for a specific query:

mysql> SET STATEMENT max_statement_time=1000 FOR SELECT name FROM name ORDER BY name;

We can provide more than one variable we want to set up:

mysql> SET STATEMENT sort_buffer_size=100000, max_statement_time=1000 FOR SELECT name FROM name ORDER BY name;

Version Specific Information

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