sql - Order by with distinct -

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firstly sql:

select distinct(cartable.carplate), cartable.carimage, eventtable.firstdate cartable join eventtable on cartable.carid = eventtable.carid order 3 desc

i trying order rows date , works fine want plates written 1 time. mean need see car's last event seems using distinct wrong. best way of doing ?

use max , group by:

select      c.carplate,      c.carimage,      firstdate = max(e.firstdate) cartable c inner join eventtable e     on c.carid = e.carid group c.carplate, c.carimage order max(e.firstdate) desc

note:

  • use meaningful alias improve readability.

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