RE: Any known problems using NOT IN ?

[Siddharth Haldankar]

Charu,   Thanks for your explanation. It is perfectly valid for me.   Thanks Siddharth Haldankar Zensar Technologies Ltd. Cisco Systems Inc. (Offshore Development Center) #  : 091 020 4128394 [EMAIL PROTECTED] [EMAIL PROTECTED]   -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Charu Joshi Sent: Thursday, December 18, 2003 11:09 AM To: Multiple recipients of list ORACLE-L Subject: RE: Any known problems using NOT IN ?   Siddharth,   The NOT IN query fails to return rows, if the inner sub-query returns NULL values. It is always recommended to use the NOT EXISTS clause, unless you are sure that the inner query will not return any NULLs.   Regards, Charu.   -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]On Behalf Of Siddharth Haldankar Sent: 18 December 2003 10:54 To: Multiple recipients of list ORACLE-L Subject: Any known problems using NOT IN ? Hi Gurus,   I have a problem using NOT IN clause in Oracle. However using NOT EXISTS, gives me the right output. Are there any known limitations.   This query selects from the master records wherein child records are not active.   select * from ct_software_release csr where   csr.class         = 'NS'   AND    csr.active_flag   = 'Y'   AND    csr.os_id_pk not IN   (SELECT crs.os_id_fk1 FROM CT_ROADMAP_SOFTWARE crs         WHERE crs.active_flag  = 'Y');   The sub-query in the above case gives 1800 rows. The above query fails to give any rows.                                                                                   select * from ct_software_release csr where   csr.class         = 'NS'   AND    csr.active_flag   = 'Y'   AND    NOT EXISTS         (SELECT 1 FROM CT_ROADMAP_SOFTWARE crs         WHERE crs.os_id_fk1 = csr.os_id_pk                                 AND crs.active_flag  = 'Y');                                                              This above query works fine.       Thanks Siddharth Haldankar Zensar Technologies Ltd. Cisco Systems Inc. (Offshore Development Center) #  : 091 020 4128394 [EMAIL PROTECTED] [EMAIL PROTECTED]     ********************************************************* Disclaimer This message (including any attachments) contains confidential information intended for a specific individual and purpose, and is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this message, or the taking of any action based on it, is strictly prohibited. ********************************************************* Visit us at http://www.mahindrabt.com