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Re: mulitple joins not quite right?
Posted by: Peter Brawley
Date: August 27, 2018 09:51AM

> SELECT *, count(e.athID) ... group by m.meetID

The "*" will return arbitrary results for all columns except meetid and athid. Read the manual page on aggregation.

> ... FROM entry_meets m
> left join entry_pack p ... where ... p.status='Accepted' ...

The Where condition on p.status effectively turns the left join into an inner join. To avoid that, write ...

select m.meetid, ifnull( p.pcount, 0 ) as entrypacks
from entry_meets m
left join (
  select meetid, count(*) as pcount
  from entry_pack
  where p.status='Accepted'
) on p.meetID = m.meetID

> get all the meets with entry counts (from entry forms that have been accepted) including meets with no entry forms?

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Re: mulitple joins not quite right?
August 27, 2018 09:51AM


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