Thank you for useful articles.
But there is problem!

in below sample (in SQL SERVER):

CREATE TABLE [Test] (
[ID] [bigint] IDENTITY (1, 1) NOT NULL ,
[Date] [char] (10),
[B] [int],
[C] [int]
)
INSERT INTO [TEST].[Test]
VALUES (’1389/01/01′,’1′,’1′)
INSERT INTO [TEST].[Test]
VALUES (’1389/01/01′,’5′,’2′)
INSERT INT[TEST].[Test]
VALUES (’1389/01/02′,’2′,’10′)
INSERT INT[TEST].[Test]
VALUES (’1389/01/02′,’2′,’11′)
INSERT INT[TEST].[Test]
VALUES (’1389/01/03′,’2′,’2′)
INSERT INT[TEST].[Test]
VALUES (’1389/01/03′,’5′,’1′)
INSERT INT[TEST].[Test]
VALUES (’1389/01/01′,’2′,’1′)
INSERT INT[TEST].[Test]
VALUES (’1389/01/02′,’2′,’12′)
INSERT INT[TEST].[Test]
VALUES (’1389/01/03′,’2′,’2′)

when we use:

select l.Date, l.B, l.C, count(*) as num
from Test as l
left outer join Test as r
on l.Date = r.Date
and l.B >= r.B
group by l.Date, l.B, l.C

we have:

…
1389/01/02 2 10 3
1389/01/02 2 11 3
1389/01/02 2 12 3
…

But must be create like :

…
1389/01/02 2 10 1
1389/01/02 2 11 2
1389/01/02 2 12 3
…

No my question:
What solve it? (Create above table)?
Note : I want use SQL only (No use TSQL)!
Note 2 : Cause problem is ‘Like Data in Date and B Field’

Description 1: My english is poor.Excuse me!
Description 2: Date is persian calender!

SELECT *, @rownum:=@rownum+1 rownum, (SELECT @rownum:=0) dummy
FROM fruits
HAVING rownum <= (pg*lim);

You'll notice I used it for dynamic paging of the result set in my stored proc.

SET @n := 0;
SET @t := NULL;
SELECT f.*, @n
FROM fruits f
WHERE CASE WHEN f.type != @t THEN @n := 0 ELSE 1 END >= 0
AND(@n := @n + 1) >= 0
AND(@t := f.type) IS NOT NULL

SET @n := 0;
SET @t := NULL;
SELECT f.*, @n
FROM fruits f
WHERE CASE WHEN f.type @t THEN @n := 0 ELSE 1 END >= 0
AND(@n := @n + 1) >= 0
AND(@t := f.type) IS NOT NULL