sql - I want to use group by function for Id,Firstname,Mark1,Mark2,Mark3 -


i have 3 tables contains parent,child,mark

in parent table:

id int(primarykey), firstname varchar(50), email varchar(50)

in child table:

mid int(primarykey), mark1 int, mark2 int, id int(foreignkey)

in mark table:

uid int(primarykey), mark3 int, id int(foreignkey)

by using query,i'm getting result.

select id, max(firstname)firstname, max(mark1) mark1, max(mark2) mark2, max(mark3) mark3 ( select id,firstname,null mark1,null mark2,null mark3 parent union select id,null firstname,mark1,mark2,null mark3 child  union select id,null firstname,null mark1,null mark2,mark3 mark ) t group id

here in query, have used group function id wanna use group function rest of column names. possible without using join query?

thanks in advance.


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