RE: full usefullness of CURRENT OF ???

From: Kevin Toepke <ktoepke_at_rlcarriers.com>
Date: Fri, 11 Jul 2003 11:24:24 -0800
Message-ID: <F001.005C462E.20030711112424@fatcity.com>

Yes, using WHERE CURRENT OF is faster. It is the same as saying "WHERE rowid = emprec.rowid", just more readable. And accesses by rowid are faster than index accesses.

Also, what happens if you don't have a unique or primary constraint on the table and whole rows can be duplicated? Then you pretty much need to use WHERE CURRENT OF. HTH
Kevin

-----Original Message-----
Sent: Friday, July 11, 2003 2:54 PM
To: Multiple recipients of list ORACLE-L

Could anyone give us an idea as to the full usefullness of CURRENT OF? Here are my two separate examples:

/* 1 this one has a CURRENT OF */

DECLARE     CURSOR EmpCursor IS

            SELECT  *
            FROM    Emp
            FOR     UPDATE;

BEGIN
     FOR EmpRec IN EmpCursor LOOP

         UPDATE EMP
         SET    SALARY = SALARY * 1.08
         WHERE  CURRENT OF EmpCursor

     END LOOP;

END; /* 2 same as above, except without the CURRENT OF */ DECLARE    CURSOR EmpCursor IS

           SELECT  *
           FROM    Emp
           FOR     UPDATE;

BEGIN
     FOR EmpRec IN EmpCursor LOOP

         UPDATE EMP
         SET    SALARY = SALARY * 1.08
         WHERE  EMP_ID = EmpRec.Emp_ID;

     END LOOP;

END;
/

Is one more efficient than the other? If I could have done business without the CURRENT OF, then why did oracle made it available?

thx
maa

--

Please see the official ORACLE-L FAQ: http://www.orafaq.net
--

Author: Maryann Atkinson
  INET: maryann_30_at_yahoo.com

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------

To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
--

Please see the official ORACLE-L FAQ: http://www.orafaq.net
--

Author: Kevin Toepke
  INET: ktoepke_at_rlcarriers.com

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------

To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). Received on Fri Jul 11 2003 - 14:24:24 CDT