Validation in customerID field

[buddythebest]

In a school, a customer ID (in a canteen for example) would be either student administration number or staff initials.... how can i make this customerID field so that it accepts either all numbers (for student admin. no.) or all text with only 3 letters (for staff initials)?


thank you plz reply soon

 

[Smart]

make sure that your customer Id field in your table has a datatype of text

 

[buddythebest]

no, i mean can i create a "validation" so that accepts only all numbers or all text (i already have it as text datatype), if it requires Visual Basic just consider that i am a complete newb in it