Execute SQL Task: Variable Mapping Failed With Complex SQL Script. Please Help!

Hi all,
I'm working with Execute SQL task. Connection type: OLE DB. With the following settings, the task works fine:

Parameter mapping:



Code Snippet

Variable Name Direction Data type Parameter Name
User::InputFile Input NVARCHAR 0
User::DesiredOutput Input NVARCHAR 1
SQLStatement:



Code Snippet

exec [spu_CreateOutput] ?, ?

However, I want to put in some conditions so I modified the task as:

Parameter mapping:



Code Snippet

Variable Name Direction Data type Parameter Name
User::OutputFile Input NVARCHAR 0
User::InputFile Input NVARCHAR 1
User::DesiredOutput Input NVARCHAR 2

SQLStatement:



Code Snippet

if(? <> 'NotUsed')
Begin
exec [spu_CreateOutput] ?, ?
End

But the modification doesn't work. The following message was thrown:

Error: 0xC002F210 at CREATE OUTPUT, Execute SQL Task: Executing the query "if(? <> 'NotUsed')
Begin
exec [spu_CreateOutput] ?, ?
End
" failed with the following error: "Syntax error, permission violation, or other nonspecific error". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established correctly.
Task failed: CREATE OUTPUT

Can anyone tell me what I have been wrong with it? It seems that parameter mapping can only apply for a single select statement/function/procedure call :-?

Thank you,
GiaHi