RE: Difference between count(1) and count(*)

From: Thomas Day <tday6_at_csc.com>
Date: Thu, 8 Jul 2004 10:23:52 -0400
Message-ID: <OFD4175376.96BC5972-ON85256ECB.004EB5C7@csc.com>

230297 rows in every case

Row Count using all columns                     Elapsed: 00:00:02.06
Row Count using a specific numbered column            Elapsed: 00:00:02.06
Row Count using the pseudo-column rownum        Elapsed: 00:00:02.08
Row Count using the ROWID column                Elapsed: 00:00:02.07
Counting a Not-NULL column                      Elapsed: 00:00:02.07
Counting a NULL column                    Elapsed: 00:00:02.06

Doesn't look like a lot of difference to me but maybe the sample is small.

                                                                                                                                       
                      "Peter Miller"                                                                                                   
                      <Peter.Miller            To:      <oracle-l_at_freelists.org>                                                       
                      @cogent-dsn.com>         cc:                                                                                     
                      Sent by:                 Subject: RE: Difference between count(1) and count(*)                                   
                      oracle-l-bounce                                                                                                  
                                                                                                                                       
                                                                                                                                       
                      07/08/2004 09:40                                                                                                 
                      AM                                                                                                               
                      Please respond                                                                                                   
                      to oracle-l

1,749,951 rows returned in every case

count(rowid) - approx 3.2 secs
count(obj#)  - approx 3.5 secs
count(1)     - approx 3.6 secs
count(*)     - approx 3.6 secs
count(rownum)- approx 4.6 secs
count(source)- approx 8.6 secs









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Received on Thu Jul 08 2004 - 10:16:28 CDT