How to write multiple count select statement in sql -

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i need combine 2 count statement 1 select. can done?

select dealer ,firstname ,producttype ,date ,comments ,count(*) total select dealer ,firstname ,valid ,comments ,count(*) invalidtotal

you use union statement create single query, return 2 rows. howwever, column name count(*) column come first query, add flag, such isvalid column in example below

  select vr.dealerid     ,vr.commissionrunid     ,vd.producttype     ,vd.valid     ,vd.comments,     1 isvalid,     ,count(*) total     union     select vr.dealerid     ,vr.commissionrunid     ,vd.valid     ,vd.comments     0 isvalid,     ,count(*) invalidtotal

however, if looking 1 row, i.e.

  select vr.dealerid     ,vr.commissionrunid     ,vd.producttype     ,vd.valid     ,vd.comments,     ,count(*) total     ,count(*) invalidtotal.

then need see how determine valid vs invalid counting purposes. doable, need create case statement returns 1 or 0 (for valid or invalid) , sum columns. without knowing sql dialect, following pseudo-code representation..

sum (case isvalid='y' 1 else 0 end) totalvalid, sum (case isvalid='n' 1 else 0 end) totalinvalid,

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