You can't do that in THAT way, but you can use dynamic SQL:
test=# select * from drop_role ;
t
--------
foobar
(1 row)
test=*# do $$ declare r text; begin for r in select t from drop_role loop
execute 'drop role ' || quote_ident(r) || ';'; end loop; end; $$language
plpgsql;
DO
"Brice André" <brice@famille-andre.be> hat am 19. Oktober 2011 um 12:11
geschrieben:
> Hello everyone,
>
> I would want to implement an SQL query where I would be able to suppress all
> information from a registered user. I am currenlty able to suppress everything
> except the user role. The name of the role is present in a table and so, I
> would want to perform something like this :
> DROP ROLE (SELECT ...)
> but this is not considered as valid, as DROP ROLE is expecting a name and not
> a text field. So, I tried the following, but with no success :
> DROP ROLE CAST((SELECT...) AS name)
>
> So, does someone knows how to handle this problem ?
>
> Regards,
> Brice
>