How to use a Global Workflow Variable in Where-Clause?

Question:
How to use a Global Workflow Variable, in a Where-Clause (e.g. in a assign data activity), in the Workflow Designer correctly?

Solution:
If you are using a numeric database field in the Where-Clause, please use the following syntax of the "SQL command":

Where-Clause:
CustomerID = GV_CustomerID

But if you are using a datebase text field in the Where-Clause, it is important that the Global Workflow Variable is written into simple quotes, like:

Where-Clause:
COMPANY = 'GV_Company'