RE: Count(*) Vs Count(1)

From: Abdul Aleem <abchaudhary-ho_at_beaconhouse.edu.pk>
Date: Mon, 18 Dec 2000 08:15:58 +0500
Message-Id: <10713.124807@fatcity.com>

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Some where in Oracle Documentation I remember reading that Oracle encouraged using Count(1) over Count(*).
HTH!
Aleem

-----Original Message-----
From: Sanjay Kumar [mailto:ora_user_at_hotmail.com] Sent: Saturday, December 16, 2000 12:51 AM To: Multiple recipients of list ORACLE-L Subject: Count(*) Vs Count(1)

Hi,

I issed the following two statements and generated a plan using Explain Plan. The table on which I tried this query was v$cache.

Select Count(*) from v$cache

Select Count(1) from v$cache

I found that the explain plan generated the same plan for both the statements. Does that mean that both the statements are equally efficient.

In my opinion, I feel that Count(1) is better than Count(*).

Kindly explain.

Thanks
Rgds
Sanjay

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S= ome where
in Oracle Documentation I remember reading that Oracle encouraged using = Count(1)
over Count(*).<o:p></o:p>

<font size=3D2 =

color=3Dnavy face=3DArial><span
style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:Arial'><=
![if =

!supportEmptyParas]> <![endif]><o:p></o:p>=

-----Original Message----- 
From: Sanjay Kumar
[mailto:ora_user_at_hotmail.com] 
Sent: Saturday, December =
16, 2000
12:51 AM 
To: Multiple recipients =
of list
ORACLE-L 
Subject: Count(*) Vs =
Count(1)

<![if =
!supportEmptyParas]> <![endif]><o:p></o:p>

Hi,</fon= t><o:p></o:p>=


<span =

style=3D'font-size:12.0pt;color:black'>&nbsp;</span></font><font
color=3Dblack><span =
style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font>=

I issed the following two statements and generated a plan using Explain Plan. = The table
on which I tried this query was v$cache.<o:p></o:p>=


<span =

style=3D'font-size:12.0pt;color:black'>&nbsp;</span></font><font
color=3Dblack><span =
style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font>=

Select Count(*) from v$cache<o:p></o:p>

<span =

style=3D'font-size:12.0pt;color:black'>&nbsp;</span></font><font
color=3Dblack><span =
style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font>=

Select Count(1) from v$cache<o:p></o:p>

<span =

style=3D'font-size:12.0pt;color:black'>&nbsp;</span></font><font
color=3Dblack><span =
style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font>=

I found that the explain plan generated the same plan for both the statements. = Does
that mean that both the statements are equally = efficient.<o:p></o:p>=


<span =

style=3D'font-size:12.0pt;color:black'>&nbsp;</span></font><font
color=3Dblack><span =
style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font>=

In my opinion, I feel that Count(1) is better than = Count(*).<o:p></o:p>=


<span =

style=3D'font-size:12.0pt;color:black'>&nbsp;</span></font><font
color=3Dblack><span =
style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font>=

Kindly explain.<o:p></o:p>

<span =

style=3D'font-size:12.0pt;color:black'>&nbsp;</span></font><font
color=3Dblack><span =
style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font>=

Thanks</= font><o:p></o:p>=


Rgds</fo= nt><o:p></o:p>=


<font size=3D2 =
Received on Sun Dec 17 2000 - 21:15:58 CST