SQL cursor variable can not use in conditions - sql

Question

any idea why my #ProductNumber cursor variable is not working if used in dynamic statement? It says "Must declare scalar variable". But this is a cursor variable. But when I used it not dynamic, it works. Thanks.
DECLARE #TargetDB NVARCHAR(50)
DECLARE #SourceDB NVARCHAR(50)
DECLARE #DateEffectiveFrom datetime
DECLARE #InsertRecords NVARCHAR(1000)
SET #TargetDB = 'MySSISDb'
SET #SourceDB = 'MySSISDb2'
SET #DateEffectiveFrom = '2013-12-29'
Declare #ProductNumber INT;
DECLARE #SqlDb NVARCHAR(Max)
DECLARE Cur1 CURSOR FOR SELECT CAST(#SqlDb AS NVARCHAR(MAX))
SET #SqlDb = 'SELECT ProductNumber From '+#SourceDB+'.dbo.Item (NOLOCK)
WHERE NOT EXISTS (SELECT 1 FROM '+#TargetDB+'.dbo.Item2
WHERE ProductNumber = '+#SourceDB+'.dbo.Item.ProductNumber)'
EXEC sp_executesql #SqlDb
OPEN Cur1
FETCH NEXT FROM Cur1 INTO #ProductNumber;
WHILE ##FETCH_STATUS = 0
BEGIN
SET #InsertRecords = 'INSERT INTO ' + #TargetDB + '.dbo.Item2(
ProductNumber, ProductName, ListPrice, BirthDate)
SELECT ProductNumber, ProductName,
ListPrice, ''' + CONVERT(nvarchar(25),#DateEffectiveFrom,120) + '''
FROM ' + #SourceDB + '.dbo.Item
WHERE ' + #SourceDB + '.dbo.Item.ProductNumber = #ProductNumber'
--WHERE ' + #SourceDB + '.dbo.Item.ProductNumber = #ProductNumber
--(this is where the problem)
EXEC sp_executesql #InsetRecords
FETCH NEXT FROM Cur1 INTO #ProductNumber;
END
CLOSE Cur1;
DEALLOCATE Cur1;

Answer 1

Shift the declaration of your cursor into the SQLDb variable. In SQL Server, at least, the cursor designation "Cur1" is accessible after the execution of #SQLDb. Also, I've moved the use of #ProductNumber to outside the literal string and fixed a typo on your second EXEC statement within the cursor while loop (#InsetRecords to #InsertRecords).
DECLARE #TargetDB NVARCHAR(50)
DECLARE #SourceDB NVARCHAR(50)
DECLARE #DateEffectiveFrom datetime
DECLARE #InsertRecords NVARCHAR(1000)
SET #TargetDB = 'MySSISDb'
SET #SourceDB = 'MySSISDb2'
SET #DateEffectiveFrom = '2013-12-29'
Declare #ProductNumber INT;
DECLARE #SqlDb NVARCHAR(Max)
SET #SqlDb = '
DECLARE Cur1 CURSOR FOR
SELECT ProductNumber
From '+#SourceDB+'.dbo.Item (NOLOCK)
WHERE NOT EXISTS (
SELECT 1
FROM '+#TargetDB+'.dbo.Item2
WHERE ProductNumber = '+#SourceDB+'.dbo.Item.ProductNumber)'
EXEC sp_executesql #SqlDb
OPEN Cur1
FETCH NEXT FROM Cur1 INTO #ProductNumber;
WHILE ##FETCH_STATUS = 0
BEGIN
SET #InsertRecords = 'INSERT INTO ' + #TargetDB + '.dbo.Item2(
ProductNumber, ProductName, ListPrice, BirthDate)
SELECT ProductNumber, ProductName,
ListPrice, ''' + CONVERT(nvarchar(25),#DateEffectiveFrom,120) + '''
FROM ' + #SourceDB + '.dbo.Item
WHERE ' + #SourceDB + '.dbo.Item.ProductNumber = ' + CONVERT(nvarchar(max), #ProductNumber)
EXEC sp_executesql #InsertRecords
FETCH NEXT FROM Cur1 INTO #ProductNumber;
END
CLOSE Cur1;
DEALLOCATE Cur1;