I had a parameter in Reporting Services with a list of user IDs. I needed to add a blank line as the first value instead of the default value of “<Select a value>”. I messed around with the parameter properties screen, including checking “Allow blank value” and “Allow null value”, but neither did what I wanted. My solution was to tweak the query a little bit.
The UserName parameter was populated with a UserNameDataSet Dataset, and that Dataset was populated with the following query:
ORDER BY UserID
Nothing fancy – the UserName field holds text user name that is used to log into the system. In order to add a blank line at the top of the list for the user UserName parameter, I had to modify the query to look like the one below, adding a new, dummy “ID” field and UNIONing in a blank space line:
SELECT UserName, 1 AS ID
SELECT ‘ ‘ AS UserName, 0 AS ID
ORDER BY UserName
Hey, it met the requirements.