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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Difference between count(1) and count(*)
Who needs count(*) or count(anything)?
Try this:
select -1/2+1/2*sqrt(1+8*sum(rownum)) from wi_cumulative;
;-)
(Shamelessly stolen from the AskTom thread, originally posted by Mikito = Harakiri.)
-Mark
-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Mladen Gogala
Sent: Thursday, July 08, 2004 10:32 AM
To: oracle-l_at_freelists.org
Subject: Re: Difference between count(1) and count(*)
On 07/08/2004 09:40:17 AM, Peter Miller wrote:
> 1,749,951 rows returned in every case
>=20> count(rownum)- approx 4.6 secs
> count(rowid) - approx 3.2 secs
> count(obj#) - approx 3.5 secs
> count(1) - approx 3.6 secs
> count(*) - approx 3.6 secs
Connected to:
Oracle9i Enterprise Edition Release 9.2.0.5.0 - Production
With the Partitioning option
JServer Release 9.2.0.5.0 - Production
=20
SQL> set timing on
SQL> select count(*) from wi_cumulative;
=20
COUNT(*)
12148659
=20
Elapsed: 00:00:20.62
SQL> select count(1) from wi_cumulative;
=20
COUNT(1)
0
=20
Elapsed: 00:00:19.12
SQL>
Tanel's favorite way of counting differed from the real count for only =
about 12 million rows,
and it wasn't that much faster, so the difference doesn't justify lack =
of precision.
--=20
Mladen Gogala
Oracle DBA
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