mysql - Select on aggregate result -


i have query count table adds column result. need alter original select results based on being told unknown column.

e.g. following query count table within main query, , result named shares, need filter main query result set based on whether column greater 0 error unknown column shares

select b.name, event_title, ue.event_vis, event_date,      (select count(*) list_shares          user_id = 63 , event_id=ue.user_event_id) shares,     (dayofyear(ue.event_date) - dayofyear(curdate())) days  brains b     join user_events ue on b.user_id=ue.user_id b.user_id=63 , ((ue.event_vis='public') or (shares>0))      , mod(dayofyear(ue.event_date) - dayofyear(curdate()) + 365, 365) <= 30  order days asc 

is there way this?

i suggest using derived table deliver aggregate value , join "phyiscal" table. example:

select     b.name,     ue.event_title,     ue.event_vis,     ue.event_date,      tmp.shares,     (dayofyear(ue.event_date) - dayofyear(curdate())) days      brains b join user_events ue on b.user_id = ue.user_id     left join (         select             ls.user_id,             ls.event_id,             count(*) shares                     list_shares ls         group             ls.user_id,             ls.event_id) tmp on b.user_id = tmp.user_id , ue.user_event_id = tmp.event_id      b.user_id = 63 ,     ((ue.event_vis = 'public') or (tmp.shares > 0)) ,      mod(dayofyear(ue.event_date) - dayofyear(curdate()) + 365, 365) <= 30   order     days asc 

please note "left join". because using or operator in clause seems me want rows without share.

of course use same subselect in clause that's duplicate code , harder maintain.


Comments

Popular posts from this blog

html - Sizing a high-res image (~8MB) to display entirely in a small div (circular, diameter 100px) -

java - IntelliJ - No such instance method -

identifier - Is it possible for an html5 document to have two ids? -