How to count the occurence of a column which is the result of a concatenation of a string and integer

Question

The data in my table looks like this:

AUDTORG | SEQUENCENO | LINE | REFERENCE | AMOUNT | 
--------------------------------------------------
ADX     | 1          | 422  | Wire1     | 10     | 
ADX     | 2          | 385  | Wire2     | 10     | 
ADX     | 2          | 335  | Wire25    | 10     | 
ADX     | 2          | 335  | Transfer  | 10     | 
BMD     | 1          | 555  | Wire4     | 10     | 

I have to: 1. concatenate: AUDTORG and SEQUENCENO 2. Count the occurence of the concatenated field NewID.

This is the result I'm looking for:

AUDTORG | SEQUENCENO | LINE | REFERENCE | AMOUNT | NewID  | Occurence |
-----------------------------------------------------------------------
ADX     | 1          | 422  | Wire1     | 10     | ADX1   | 1         |
ADX     | 2          | 385  | Wire2     | 10     | ADX2   | 3         |
ADX     | 2          | 335  | Wire25    | 10     | ADX2   | 3         |
ADX     | 2          | 335  | Transfer  | 10     | ADX2   | 3         |
BMD     | 1          | 555  | Wire4     | 10     | BMD1   | 1         |

Here is the code I tried:

SELECT *, BKENTD.AUDTORG + CAST(BKENTD.SEQUENCENO AS varchar) as NewID,
count(BKENTD.AUDTORG + CAST(BKENTD.SEQUENCENO AS varchar)) as Occurence
FROM ADXDAT.dbo.BKENTD

All the rows must remain.

Answer 1

You can do this using window functions:

SELECT b.*,
      (b.AUDTORG + CAST(b.SEQUENCENO AS varchar(255)) )as NewID,
      count(*) over (partition by b.AUDTORG + CAST(b.SEQUENCENO AS varchar(255)) ) as Occurence
FROM ADXDAT.dbo.BKENTD b;

The over clause is used by window function. In this case, it counts everything in a group. The group is defined by the partition by clause. So, it counts everything with the same value of the new id.

Answer 2

All rows must remain makes for the need for a subquery. This will obtain counts:

select BKENTD.AUDTORG + CAST(BKENTD.SEQUENCENO AS varchar) as NewID, count(*) Occurence
FROM ADXDAT.dbo.BKENTD
group by BKENTD.AUDTORG + CAST(BKENTD.SEQUENCENO AS varchar)

You now have the NewID and count for each. Join it back to your first statement and refer to it as a standard column (select * is now select a.* so you don't get the b.newID field):

SELECT a.*, BKENTD.AUDTORG + CAST(BKENTD.SEQUENCENO AS varchar) as NewID, Occurence
FROM ADXDAT.dbo.BKENTD a
inner join 
(select BKENTD.AUDTORG + CAST(BKENTD.SEQUENCENO AS varchar) as NewID, count(*) Occurence
FROM ADXDAT.dbo.BKENTD
group by BKENTD.AUDTORG + CAST(BKENTD.SEQUENCENO AS varchar)) b
on a.NewID = b.NewID