Oracle 12c: using user defined functions results and In Clause

Question

I have a function(funct_A) that returns a varchar in quotes Select funct_A from dual returns 'A1234';

I want to use the result from funct_A in an IN clause

This returns 100 --> select count(E.tickets) from event E where E.ticket_number in ('A1234').

This returns 0 --> select count(E.tickets) from event E where E.ticket_number in (funct_A).

How is this accomplished?

How is this accomplished.

Answer 1

You probably wouldn't. If your function always returns a single value, you'd just use an equality condition rather than an IN . Assuming your actual goal, though, is for the function to return multiple values, you likely want a pipelined table function instead

create or replace type ticket_tbl is table of varchar2(10);

create or replace function funcA
  return ticket_tbl
  pipelined
is
begin
  pipe row ('A1234');
  pipe row ('B5678' );
end;
/

select *
  from event e  
 where e.ticket_number in (select column_value
                             from table( funcA ) );