Test This #5 – Null vs. Blank
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If your AUT has logic that checks for null values, make sure removed values get set back to null. If they get set to blank, you may have a nice crunchy bug.
Here are the pseudo steps for the test case using a generic order form example. But you can use anything in your AUT that programmatically makes a decision based on whether or not some value exists.
Feature: Orders with missing line item quantities can no longer be submitted.
- Create a new line item on an order. Do not specify a quantity. Crack open the DB and find the record with the unpopulated quantity. Let’s assume the quantity has a null value.
- Populate the quantity via the AUT .
- Clear the quantity via the AUT. Look at the DB again. Does the quantity have a blank or null value?
Expected Results: Quantity has a null value.
If your dev only validates against null quantity values, your user just ordered nothing…yikes!

