Using 'NOT IN' Within a SQL Statement

Question

Does anyone know why the following SQL statement does not return any values? The problem is with the SELECT statement within the 'NOT IN' clause. When explicitly typing in the part_ids returned from the select statement, everything works as expected.
Thanks for any help.
SELECT Distinct Part_Id, Trans_Date
     FROM Invctrl
     WHERE Trans_Type = 0
     AND Trans_Date BETWEEN To_Date( '1-Mar-2006 00:00:00', 'dd-mon-yyyy hh24:mi:ss' )
     AND To_Date( '31-Jan-2007 23:59:59', 'dd-mon-yyyy hh24:mi:ss' )               
     AND Part_Id NOT IN (SELECT part_Id From InvCtrl WHERE Trans_Date < To_Date( '1-Mar-2006 00:00:00', 'dd-mon-yyyy hh24:mi:ss'))

Answer 1

'NOT IN' should be avoided where ever we can.
Change your query to 'IN' clause as below and it should work.
SELECT DISTINCT part_id, trans_date
           FROM invctrl
          WHERE trans_type = 0
            AND trans_date BETWEEN TO_DATE ('1-Mar-2006 00:00:00',
                                            'dd-mon-yyyy hh24:mi:ss'
                               AND TO_DATE ('31-Jan-2007 23:59:59',
                                            'dd-mon-yyyy hh24:mi:ss'
            AND part_id IN (
                   SELECT part_id
                     FROM invctrl
                    WHERE trans_date BETWEEN TO_DATE ('1-Mar-2006 00:00:00',
                                                      'dd-mon-yyyy hh24:mi:ss'
                                         AND TO_DATE ('31-Jan-2007 23:59:59',
                                                      'dd-mon-yyyy hh24:mi:ss'
                   MINUS
                   SELECT part_id
                     FROM invctrl
                    WHERE trans_date <
                             TO_DATE ('1-Mar-2006 00:00:00',
                                      'dd-mon-yyyy hh24:mi:ss'
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