Search using blank variable
I am trying to create a Find Utility of sorts to help new users quickly sort through my company's records. Using the "Input Fields" option of the "Show Custom Dialogue" action, I am prompting the user to enter an Part Number, a Serial Number, and a Customer Number.
Please Enter The Following:
Customer Number: _______
Serial Number: __________
Part Number: ___________
My goal is to allow the user to add any one of (or all of) the three items to produce found results. However, if the user leaves, say, the serial number blank, the assignment of the input value to a variable $serial which is then searched puts the string "$serial" into the find field.
Is there a way to have the find simply ignore the blank variable and only search with the non-empty values?
....I apologize, my wording/vocabulary isn't very clear...