On 2007-09-19, Christoph Krammer <redtiger84@googlemail.com> wrote:
> Hello everybody,
>
> I have two rather large table with TEXT fields where I need to do a
> JOIN. All fields that are used in the JOIN and should be part of the
> result are covered in an index, but the JOIN still uses temporary
> tables and takes three hours (!) to complete.
>
> This is my schema:

<snip>

Try forcing the index use:
http://dev.mysql.com/doc/refman/5.0/en/index-hints.html