Re: Partitioning and JOIN

[Rick James]

I see nothing to tell it how to prune the second table. Is are the 'created' columns the same for each match? If so, then this might work:

select  count(*)
    from  session as s
        left join  action as a on s.id = a.session_id
    where  s.created >= '2007-03-01'
      and  s.created <= '2007-03-31 23:59:59'
      and  a.created >= '2007-03-01'
      and  a.created <= '2007-03-31 23:59:59'

Isn't the pruning field (created) supposed to be part of the PRIMARY KEY?