count(1) and count(*) give the same result - both count null values - a
count on a specific column does not count null values - see example below
The result set is the same, but the performance may differ.

SQL> desc x
Name Null? Type
----------------------------------------- --------
----------------------------
N NUMBER
V VARCHAR2(5)

SQL> select * from x;

N V
---------- -----
1 a
2
c

SQL> select count(1) from x;

COUNT(1)
----------
3

SQL> select count(*) from x;

COUNT(*)
----------
3

SQL> select count(n) from x;

COUNT(N)
----------
2

SQL> select count(v) from x;

COUNT(V)
----------
2



|---------+--------------------------------------------------------->
| | "Edwin Uy " |
| | <oracledba-ezmlmshield-x93770188.[Email Address Removed] | azydba.com> |
| | |
| | 06/02/2004 07:05 AM |
| | |
|---------+--------------------------------------------------------->
>----------------------------------------------------------------------------------------------|
| |
| To: "LazyDBA.com Discussion" <> |
| cc: |
| Subject: Just out of curiosity |
>----------------------------------------------------------------------------------------------|




Hi all,



select count(*) or select count(1) . does it really matter . ???



Cheers,

EDWIN ONG UY
\\|//
(o o)
^"^"^"^"^"^oOOo"^(_)^"oOOo^"^"^"^"^"^"^"^"^"^"^

"Choose a job you love, and you will never have to work a day in your
life." --Confucius
"How do I work? I grope." -- Albert Einstein
"Experience is the best teacher, enrolling in the class is the biggest
problem." -- Anonymous





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