Please can someone provide an overview of how to select all records in the parameter list. I am trying to get an understanding of how this works.

Having a union join with all value is fine, to retrieve the value of 'all'. However, given the data-set there is no 'all' value. From reading the ms course notes, the query syntax is: select from where = (field = @x) or @x = 'all'. How does this syntax work? Does x = all, so all= all = true then returns all records?

Regards,

Nijojo