Arithmetic with columns in different tables in mysql [optmization] -

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in following query:

select    (select nick nicks n n.pid=p.id limit 1 order id desc) nick   , (           (              ( select count(*) kills k k.pid = p.id )               +               ( select count(*) votos v v.pid = p.id )            )            - (select count(*) deaths d d.pid = p.id )   ) score   , (select count(*) kills k k.pid = p.id ) kills   , (select count(*) deaths d d.pid = p.id ) deaths   , (select count(*) headshots h h.pid = p.id ) headshots   , (select count(*) votos v v.pid = p.id ) reputation  players p p.uuid='steam_x:x:xxxxxx' group kills

this query works fine... think there exists better way this. can me optimize query?

enter image description here

here better way write query:

select p.*, (kills + reputation - deaths) score (select (select nick nicks n n.pid = p.id order id desc limit 1              ) nick,              (select count(*) kills k k.pid = p.id ) kills,              (select count(*) deaths d d.pid = p.id ) deaths,              (select count(*) headshots h h.pid = p.id ) headshots,              (select count(*) votos v v.pid = p.id ) reputation       players p       p.uuid = 'steam_x:x:xxxxxx'      ) p group kills;

note: don't understand group by doing. aggregating 1 column, rest of columns have indeterminate values. perhaps intend order by.

i guessing overhead materializing subquery before group by less additional subqueries. version may have comparable performance.

for either version, want following indexes:

  • players(uuid)
  • kills(pid)
  • deaths(pid)
  • headshots(pid)
  • votos(pid)

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