Convert Decimal to String on Pivot - sql

Question

example Code
Declare
#table1 VARCHAR(MAX)
Set #table1 = 'Select * from #tempTbl'
Declare
#List VARCHAR(MAX),
#Pivot VARCHAR(MAX)
Select #List = ISNULL(#List + ',', '') + TrxCd From TransacMaster Where Module = 'CB'
Set #Pivot = '
SELECT ROW_NUMBER() OVER (ORDER BY DebtorCd ASC) As RowIndex, *
FROM (
Select Distinct
c.UserId,
d.Name,
b.TrxCd
SUM(b.Amount) As Amount
From tbl_InvH a
Inner Join tbl_InvD b on a.subCd = b.subCd and a.InvNo = b.InvNo
Left Join tbl_User c On a.UserId = c.UserId
Left Join tbl_Personnel d on c.PersonnelId = d.PersonnelId
Group By c.UserId, d.Name, b.TrxCd
) as s
PIVOT
(
SUM(Amount)
FOR TrxCd IN (' + #List + ')
)AS pvt'
Declare #Result nVarchar(MAX)
Set #Result = #table1 + '
Union All
' + #Pivot
Exec sp_executesql #Result
I want to Convert Field Amount from decimal to String, because after this I want to UNION with another tables, but field amount and field from another table is different type.
I have tried CAST(SUM(Amount) as Varchar) But Error :
'CAST' is not a recognized aggregate function.
I can't Convert on Main Select because Field of TrxCd is Dynamic
Result Of Pivot
RowIndex | UserId | Name | IT01 | IT02 | IT03 | IT04
--------------------------------------------------------------------------------
1 | John | John Ivy | 2,000 | 2,000 | 1,000 | 5,000
2 | Merry | Merry Ish | 1,000 | 1,000 | 1,000 | 6,000
other Table
RowIndex | UserId | Name | Transac1 | Transac2 | Transac3 | Transac4
-------------------------------------------------------------------------------------------------
1 | John | John Ivy | Trx Bank A | Trx Bank B | Trx Bank C | Trx Bank D
What should I do to Convert Field Amount from Pivot.

Answer 1

Because of the dynamic nature, you could take the same #List expression Select #List = ISNULL(#List + ',', '') + TrxCd From TransacMaster Where Module = 'CB' and create a second for the dynamic casting in the main select;
Select #List2 = ISNULL(#List2 + ',', '') + 'cast(' + TrxCd + 'as varchar)' From TransacMaster Where Module = 'CB'
Then use this and additional columns required to replace the asterix in the main select;
'SELECT ROW_NUMBER() OVER (ORDER BY DebtorCd ASC) As RowIndex, UserId, Name,' + #List2 +'....'