When I make table records I almost always use a randomstring as the ID. Sometimes, though, you might want to autoincrement. This quick tip explains one way to do that.
This is an awesome quick tip @freedman!
Adding on to this, if you want to enforce the number of characters in the auto increment you can use an expression such as below to create IDs which start with 0000001 and go to 9999999.
RIGHT('000000' + (TEXTTOINTEGER(@Table Aggregation.Mode ) + 1), 7)
Or something like this to go from WO0000001 to WO9999999
'WO' + RIGHT('000000' + (TEXTTOINTEGER(@Table Aggregation.Mode ) + 1), 7)