Unexpected loooong response time when asking for specific information in select

[Stefan Engstr?m]

My mysql is responding strangely to a select when I try to ask for
particular columns instead of everything. Here is an example which is
querying a database of
a few thousand elements in each table.

This query works well and responds in less than a second:
select * from measure as m1, measure as m2, pairs as p where
m1.geneid=p.geneid
and m1.exp=p.exp1 and m2.geneid=p.geneid and m2.exp=p.exp2 order by
p.geneid

If I try to be specific and replace * with p.*, p.geneid or anything
more specific, mysqld appears to takes a lunch break and comes back
after 40-50 minutes with the correct information. The same problem
happens if I don't use 'pairs as p' but refer to that table with its
full name. Strange, huh?

Any suggestions would be greatly appreciated!

Stefan Engstrom

mysql --version says:
Ver 11.18 Distrib 3.23.58, for redhat-linux-gnu (i386)