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Re: MySQL 5.1 does not seem to be using the index that I expect it to.
Posted by: Tom Muldoon
Date: April 03, 2011 05:40PM

Hi RIck,

your assumptions regarding the query are correct. With that said, I tried the query per your suggestion...

EXPLAIN
select id, trigger_time, note, type, status,
notification_status, submission_id,
actor_id, actor_display_name, actor_user_type,
recipient_id, recipient_display_name,
recipient_user_type, system_id,
from activity_event
where recipient_id=1
order by trigger_time ASC, id ASC;

... and here's the explain plan (it does not use the expected index)...

'1', 'SIMPLE', 'activity_event', 'ref', 'recipient_id__status__trigger_time__id,recipient_id__trigger_time__id', 'recipient_id__status__trigger_time__id', '8', 'const', '333', 'Using where; Using filesort'

I'm afraid that I don't know what you mean by "(Use [ code ] before, and [ /code ] after (without spaces).)".

Tom

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