mysql - Select fields from table with DISTINCT field -

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i have table of type

 | user | parents | sons |

with

  • parents , sons columuns can null.
  • user column can contains duplicated

i write query:

select user, coalesce(parents, 0) parentsed, coalesce(sons, 0) sonsed    my_table    order (parentsed + sonsed) desc

and works! give result duplicated users. how can have distinc users using (parentsed + sonsed) desc order ?

use group by before order clause , if want order results first group them use subselect 

select `user`, coalesce(parents, 0) parentsed, coalesce(sons, 0) sonsed  my_table group `user` order (parentsed + sonsed) desc  select distinct `user`, coalesce(parents, 0) parentsed, coalesce(sons, 0) sonsed  my_table  order (parentsed + sonsed) desc   select a.* ( select distinct `user`, coalesce(parents, 0) parentsed, coalesce(sons, 0) sonsed  my_table  order (parentsed + sonsed) desc ) group a.`user`

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