Are there way to controll the memory usage per user in MySQL.MyISAM?

Question

In the interactive query form sometimes my users are making wrong joins and query generates huge amount of data after doing while. How can I prevent the user to use more than certain amount of memory?
I would like to limit the memory usage per query...

I am using mysql 5.5.8 myisam engine.
Thanks Arman.

Answer 1

No, MySQL has no per-user memory quota ability.

How much memory a single query can use is dictated by many variables you can configure. You can limit the size of join buffers, sort buffers, temporary tables, etc. These limits will be global for all queries.

Answer 2

I don't think MyISAM let's you control this on a per thread basis.

You can always use

SHOW PROCESSLIST

and KILL any processes that have been running for certain length of time.