Hi Everyone,
Can anyone suggest why the following query is taking upwards of 5
seconds to run?
SELECT * FROM users
JOIN sites ON users.ID = sites.userid
WHERE users.username = 'user1234'
OR users.email = 't...@test.com'
OR sites.email = 't...@test.com' <mailto:'ccf...@googlemail.com'>
The users table has an index on the username field and another on the
email field.
The sites table has an index on the email field.
Both tables contain around 200k rows.
An explain of the query shows that no indexes are being used:
id select_type table type possible_keys key key_len
ref rows Extra
1 SIMPLE users ALL PRIMARY,username,email NULL NULL
NULL 155424
1 SIMPLE sites ref userid,email userid 4
dyos.users.ID 1 Using where
Can anyone tell me how to make it use the available indexes? Or do I
need to add some sort of multi-column index? I'm guessing not as I'm
doing OR's
Thanks
Simon