Re: [SQL] Simple SQL question

[Daniel Henrique Alves Lima]

Thank you, Jeremy.

I've built a function that returns a string from (cd_teacher, cd_course) 
and i've create a functional index over this function, like :

create index teacher_course_idx on teacher_course 
(build_unique_2p(cd_teacher,cd_course));
select * from teacher_course where build_unique_2p(cd_teacher,cd_course) 
in ('1:2','23:11','563','341');

Is it possible to use "array cast" over cd_teacher and cd_course (just 
an idea, i don't known the sintaxe), like:

select * from teachar_course where cast((cd_teacher,cd_course) as array) 
in ('{1,2}','{23,11}','{563,341}');

?

I'm using postgreSQL 7.34

Thanks !!!

Jeremy Semeiks wrote:

You could use a subselect of unions:

select * from teacher_course where (cd_course, cd_teacher) in
(select 1, 2 union select 23, 11 union select 563, 341)
Maybe there's a more concise way, though.

- Jeremy

 



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