Would this be an appropriate situations for a cursor? - tsql

Question

I have the following script:
SELECT left(SHI.FSOKEY, 6) AS [SoNo]
, substring(SHI.FSOKEY, 7, 3) AS [So Item]
, right(SHI.FSOKEY, 3) AS [So Rels]
, QAL.FCLOT AS [LotSerial]
FROM shmast SHM
INNER JOIN shitem SHI
ON SHM.FSHIPNO = SHI.FSHIPNO
INNER JOIN qalotc QAL
ON SHM.FSHIPNO = Left(QAL.FCUSEINDOC, 6)
AND substring(QAL.FCUSEINDOC, 7, 6) = SHI.FITEMNO
This produces output that looks like this:
SoNo So Item SoRels LotSerial
123456 1 001 ABCD
123456 1 001 AMOH
123456 1 001 POWK
123456 1 001 IUIL
123456 1 002 ABCE
I want to group by SoNo, SoItem, SoRels and get a list of LotSerials for each. So, my output would look like this:
SoNo So Item SoRels LotSerial
123456 1 001 ABCD, AMOH, POWK, IUIL
123456 1 002 ABCE
I need to do so that I can pull this information back into a main query based on the SoNo, SoItem, SoRels.
Any help would be greatly appreciated.

Answer 1

As always, avoid cursors whenever possible. Your scenario would be a good fit for a user defined function. I simplified your schema a little for this example. Essentially we are concatenating the serials that match with commas to a variable within a user defined function, and then retuning the result. If Null values are possible, you might want to add usage of Coalesce
create table SO (SONO int)
insert into SO values (1)
insert into SO values (2)
insert into SO values (3)
create table SOCHILD
(SONO int, SerialNo varchar(10))
insert into SOCHILD values (1, 'ABCD')
insert into SOCHILD values (1, 'EFGH')
insert into SOCHILD values (1, 'IJKL')
GO
create function fx_GetSerials(#SONO int)
returns varchar(1000) as
Begin
Declare #ret varchar(1000)
set #ret = ''
Select #ret = #ret + SerialNo + ','
from SOCHILD where SONO = #SONO
if (len(#ret) > 0)
set #Ret = left(#ret, len(#ret) -1)
return #ret
End
GO
select dbo.Fx_GetSerials(1)
drop function fx_GetSerials
Drop table SO
Drop table SOCHILD
Results
ABCD,EFGH,IJKL

Answer 2

#cmsjr beat me to it with his answer which is just bout the same. I do build the string differently, and have a complete working example.
try this:
CREATE TABLE YourTable (SoNo int, SoItem int, SoRels char(3), LotSerial char(4))
go
INSERT INTO YourTable VALUES (123456,1,'001','ABCD')
INSERT INTO YourTable VALUES (123456,1,'001','AMOH')
INSERT INTO YourTable VALUES (123456,1,'001','POWK')
INSERT INTO YourTable VALUES (123456,1,'001','IUIL')
INSERT INTO YourTable VALUES (123456,1,'002','ABCE')
go
CREATE FUNCTION LotSerial_to_CVS(#SoNo int, #SoItem int, #SoRels char(3))
RETURNS varchar(2000) AS
BEGIN
DECLARE #cvs varchar(2000)
SELECT #cvs=ISNULL(#cvs+', ','')+LotSerial
FROM YourTable
WHERE SoNo=#SoNo AND SoItem=#SoItem AND SoRels=#SoRels
RETURN #cvs
END
go
SELECT
SoNo, SoItem, SoRels, dbo.LotSerial_to_CVS(SoNo, SoItem, SoRels)
FROM YourTable
GROUP BY SoNo, SoItem, SoRels
OUTPUT:
SoNo SoItem SoRels
----------- ----------- ------ -----------------------
123456 1 001 ABCD, AMOH, POWK, IUIL
123456 1 002 ABCE
(2 row(s) affected)

Answer 3

There is no need for a cursor in almost ANY case any more.
You can do the same thing using XML PATH as well. Here is a working sample:
SET NOCOUNT ON
Declare #MyTable Table
(
SoNo VarChar (100),
SoItem VarChar (100),
SoRels VarChar (100),
LotSerial VarChar (100)
)
INSERT INTO #MyTable Values ('123456', '1', '001', 'ABCD')
INSERT INTO #MyTable Values ('123456', '1', '001', 'AMOH')
INSERT INTO #MyTable Values ('123456', '1', '001', 'POWK')
INSERT INTO #MyTable Values ('123456', '1', '001', 'IUIL')
INSERT INTO #MyTable Values ('123456', '1', '002', 'ABCE')
SELECT
SoNo,
SoItem,
SoRels,
STUFF ((
SELECT ', ' + LotSerial
FROM #MyTable T1
WHERE 1=1
AND T1.SoNo = T2.SoNo
AND T1.SoItem = T2.SoItem
And T1.SoRels = T2.SoRels
FOR XML PATH ('')
), 1, 2, '') AS LotSerial
FROM #MyTable T2
GROUP BY SoNo, SoItem, SoRels