🚀 go-pugleaf

Hi! I'm writing a stored procedure, for this table:

CREATE TABLE TEMPORALPRUEBA1 (
  CLIENTID INTEGER,
  DATE2 DATE,
  DATE1 DATE,
  GENE INTEGER NOT NULL);


first I select the max and min CLIENTIDs and store them in the MAXCLIENTID and MINCLIENTID variables this works fine, although I'm not sure this is the way to do it:

SELECT MAX(CLIENTID) FROM TEMPORALPRUEBA1 INTO :MAXCLIENTID;
SELECT MIN(CLIENTID) FROM TEMPORALPRUEBA1 INTO :MINCLIENTID;

But then I need to select using the variable MINCLIETNID as a condition and store it in the variable IDMAX: 

 SELECT MAX(GENE) FROM TEMPORALPRUEBA1 WHERE 
 CLIENTID = MINCLIENTID  INTO :IDMAX;

and I'm getting the error
 Column unknown MINCLIENTID.

MINCLIENTID is the name of a variable in the procedure:
DECLARE VARIABLE MAXCLIENTID SMALLINT;
DECLARE VARIABLE MINCLIENTID SMALLINT;

I'm writing the procedure in EMS SQL MANAGER 2005 for InterBase/ firebird and I'm getting the error when I compile the procedure