Count of unique rows

murugan_mf · Posted: Tue Sep 30, 2008 9:08 am Post subject: Count of unique rows

Hi all,
I have table with the following colomns.
x char(10)
y char(15)

Sample rows:
x y
-- ---
12 abc
13 qwe
13 qwe
19 xyz
21 xyz
21 xyz
o/p--4

Here I want the count of unique rows of both x and y to gether.
Can any one suggest me the query?

birdy K · Posted: Tue Sep 30, 2008 10:55 am Post subject:

Hi,

Select x,y,count(*) from table a where not exists(select ' ' from table b where a.x=b.x and a.y=b.y having count(*) > 1) group by x,y.

But I have a doubt Why you need the count. Anyway the unique rows count will be 1. Isnt it?. Corrections are welcome.

birdy K · Posted: Tue Sep 30, 2008 11:48 am Post subject:

The correction in my query.

Sachinincsc · Posted: Wed Oct 01, 2008 7:39 pm Post subject:

SELECT COUNT(*) FROM ( SELECT DISTINCT...)

Try this..