SQL Order By issue with UNION -


i have 2 sql queries using union. 

select     studentid      student   union   select     coursename      course;

if want order result coursename, how can that?

if try following gives me error. 

select    studentid     student   union   select    coursename     course  order    coursename ;

first of columns have same in both unified select's. i'm not sure, doesn't in case (because of studentid , coursename - sounds number , varchar).

however, if that's case, put sub-select , sort result:

select *    (select studentid col           student           union          select coursename col           course)  order col;

p.s. stephan pointed out correctly don't need sub select here:

select studentid col   student   union  select coursename col   course                                  order col;

reason way how union works.

p.p.s. see fiddles here: oracle , mysql.

please note: as typical mysql. if use oracle remove it.

cheers!


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