Question

I am trying to create my first procedure on firebird 2.5 by using ibexpert gui.

The procedure will return ‘PROCESS_DATE’ which belongs to a specific ‘PROCESS_ID’. I prepared following code:

begin
  OUTPUT_DATE = (select PROCESS_DATE from PROCESSES
                 where PROCESS_ID = INPUT_ID);
  suspend;
end

input parameter : ‘INPUT_ID’ –> type ‘INTEGER’
output parameter : ‘OUTPUT_DATE’ –> type ‘DATE’

But when I tried to compile it returns this error:

Column does not belong to referenced table.
Dynamic SQL Error.
SQL error code = -206.
Column unknown.
INPUT_ID.
At line 9, column 48.

I do not know how to deal with this error.

I tried to find solutions on other questions also the internet but i couldn’t find a basic, understandable answer for beginners. thanks for helps.

Answer 1

Try this:

CREATE PROCEDURE MyP (INPUT_ID INTEGER)
  RETURNS (OUTPUT_DATE DATE)
AS 
BEGIN
  FOR
    SELECT PROCESS_DATE FROM PROCESSES
    WHERE PROCESS_ID = :INPUT_ID  
    INTO :OUTPUT_DATE
  DO
    SUSPEND;
END

Always prepend parameter names with “:”. The only place where “:” is not allowed is at the left side of “=” operator.