Comments on: SQL Puzzle: SQL Advance Query – Group and Count of Consecutive flags

By: Jerry

Jerry — Sat, 04 May 2019 12:08:28 +0000

;WITH CTE
AS
(
SELECT id,flag,LAG(flag)OVER (ORDER BY id)lg,IIF(flag=(LAG(flag)OVER (ORDER BY id)),0,1)R
FROM tbl_flags
),
CTE2
AS
(
SELECT id,flag,SUM(R)OVER(ORDER BY id)S
FROM CTE
)
SELECT flag,COUNT(S)
FROM CTE2
Group By flag,S

By: Anvesh Patel

Anvesh Patel — Tue, 13 Feb 2018 18:32:13 +0000

In reply to Sql. Yes!

By: Sql

Sql — Tue, 13 Feb 2018 06:15:25 +0000

why did u use id- ROW_NUMBER() OVER (PARTITION BY flag ORDER BY id) rnk ?
Just for grouping? Thanks.

By: Dinesh.IS

Dinesh.IS — Mon, 23 Oct 2017 10:41:28 +0000

Declare @Result Table(ID Int,SLNo Int)
Declare @ID As Int,@Val Int=”,@RowCnt Int,@PVal Int=”;
Select @ID=Min(ID) From TBL_Flags
Set @RowCnt=1;

While @ID Is Not Null
Begin
Select @Val=Flag From TBL_Flags Where ID=@ID

If @PVal@Val
Begin
Set @RowCnt=@RowCnt+1
End

Insert Into @Result
(ID,SLNo)
Values(@Val,@RowCnt)

Select @ID=Min(ID) From TBL_Flags Where ID>@ID

Set @PVal=@Val

End

Select ID As FLag,Count(SLNo) As NoOfCnt From @Result
Group By ID,SLNo
Order By ID,SLNo