RE: OR Vs UNION

SET TIMING ON
SET AUTOTRACE TRACEONLY
>----- ------- Original Message ------- -----
>From: [EMAIL PROTECTED]
>To: Multiple recipients of list ORACLE-L
><[EMAIL PROTECTED]>
>Sent: Mon, 23 Jun 2003 21:34:52
>
>
>
>
>
>Hi All,
>
>Could someone explain to me which one is best in
>the following two queries
>w.r.t performance?
>
>Thanks
>Sami
>
>Query1)
>========
>select distinct empployee_id from employees where
>department_id=10 or
>department_id=20
>/
>
>Query2)
>=======
>select employee_id from employees where
>department_id=10
>union
>select employee_id from employees where
>department_id=20
>/
>
>
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>http://www.orafaq.net
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>Author:
> INET: [EMAIL PROTECTED]
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Regards,

Stephane Faroult
Oriole

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Stephane Faroult
  INET: [EMAIL PROTECTED]

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