sql server - How to select columns that dont need grouping by -

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i want select students highest grades compared brothers/sisters sql keeps saying need group firstname.

create table t (   id int,   fname  varchar(30),   lname  varchar(30),   grade int ); insert t values (3,'peter','yakobo',33), (2,'ara','yakobo',21), (1,'war','jones',45), (0,'ororo','jones',46);  select fname,lname,max(grade) t group lname

like example: in yakobo family, peter has highest grade, , in jones family ororo has highest grade

use row_number

with cte as(     select *,         rn = row_number() over(partition lname order grade desc)     t ) select     id, fname, grade cte rn = 1

as commented zlk:

you want use rank(), not row_number(), in case there duplicates.


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