How to use pivot for columns of type varchar - sql

Question

My table is:
SBType|SBName|Qty
===================
SMDB SB01 1
SMDB SB01 4
SMDB SB02 2
SMDB SB02 5
SMDB SB03 3
SMDB SB03 6
My desired output is:
SB01 | SB02 | SB03
==================
1 2 3
4 5 6
This is what my code looks like:
SELECT *
FROM (
SELECT
SM.SBName,ISNULL(ES.Qty,0)Qty
FROM RE_ES_SwitchBoard_Mast SM
left outer join RE_ES_Estimations ES on SM.PrCode=ES.PrCode and
Sm.SBType=ES.SBType and SM.SBName=ES.SBName
Where SM.PrCode='PR004' and SM.SBType='SMDB'
) as s
PIVOT
(
Max(Qty)
FOR [SBName] IN (SB01, SB02, SB03)
)AS pvthere
and the result of my attempt looks like:
SB01 SB02 SB03
1 2 3
I have tried with MAX(Qty) but it is not working.
Thanks in advance.

Answer 1

You are almost there.
By adding ROW_NUMBER() OVER (PARTITION BY SBName ORDER BY Qty) rn to the source of PIVOT clause you get multiple rows for different SBName instead of one grouped row. Your query should look like:
SELECT SB01, SB02, SB03
FROM (
SELECT
ROW_NUMBER() OVER (PARTITION BY SB.SBName ORDER BY Qty) rn,
SB.SBName,ISNULL(ES.Qty,0) Qty
FROM RE_ES_SwitchBoard_Mast SM
left outer join RE_ES_Estimations ES on SM.PrCode=ES.PrCode and
Sm.SBType=ES.SBType and SM.SBName=ES.SBName
Where SM.PrCode='PR004' and SM.SBType='SMDB'
) as s
PIVOT
(
Max(Qty)
FOR [SBName] IN (SB01, SB02, SB03)
)AS pvthere
A verifiable example here:
CREATE TABLE #sample
(
SBType varchar(MAX),
SBName varchar(MAX),
Qty int
)
INSERT INTO #sample VALUES ('SMDB','SB01',1)
INSERT INTO #sample VALUES ('SMDB','SB01',4)
INSERT INTO #sample VALUES ('SMDB','SB02',2)
INSERT INTO #sample VALUES ('SMDB','SB02',5)
INSERT INTO #sample VALUES ('SMDB','SB03',3)
INSERT INTO #sample VALUES ('SMDB','SB03',6)
SELECT SB01, SB02, SB03
FROM (
SELECT
ROW_NUMBER() OVER (PARTITION BY SBName ORDER BY Qty) rn, SBName,ISNULL(Qty,0) Qty
FROM #sample
) as s
PIVOT
(
Max(Qty)
FOR [SBName] IN (SB01, SB02, SB03)
) AS pvthere
DROP TABLE #sample

Answer 2

Dynamic query is the only way to use varchar columns in pivot. Have a look at below code to get idea.
First step is to generate comma separated list of items for column you need to use in pivot.
Then you can use this generated list in dynamic query for pivot columns.
Note: For example purpose I have used temp table. Replace it with your actual table.
CREATE TABLE #temptable
(
SBType VARCHAR(20),
SBName VARCHAR(20),
Qty INT
)
INSERT INTO #temptable SELECT 'SMDB','SB01',1
INSERT INTO #temptable SELECT 'SMDB','SB01',4
INSERT INTO #temptable SELECT 'SMDB','SB02',2
INSERT INTO #temptable SELECT 'SMDB','SB02',5
INSERT INTO #temptable SELECT 'SMDB','SB03',3
INSERT INTO #temptable SELECT 'SMDB','SB03',6
SELECT * FROM #temptable
DECLARE #cols AS NVARCHAR(MAX)
SELECT #cols = STUFF((SELECT ',' + QUOTENAME(SBName)
from #temptable
group by SBName
order by SBName
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
SELECT #cols
DECLARE #query NVARCHAR(MAX)
SET #query = '
SELECT *
FROM
(
SELECT SBType,SBName,Qty,
row_number() over (partition by SBName order by Qty) as rn
FROM #temptable
) src
PIVOT
(
MIN(Qty)
FOR SBName IN (' + #cols + ')
) piv;'
EXEC(#query)
DROP TABLE #temptable