It is common to find a simple Telephone Number field with a set of instructions attached to it: “Please don’t use spaces, dashes or brackets”… “Use brackets, don’t use spaces”… “Area code in brackets, no spaces”.
Yes, the database expects a clear format and this is very important, but the user shouldn’t have to pay for it.
All forms and specific fields should be designed taking a user-friendly approach, utilizing client side scripting to format the data, no matter how the user inputs the information.
Using the telephone example, the user should be allowed to input dashes, spaces, brackets; the script will strip these characters sending only the information needed.
Other alternative is to use a multi-field format with properly labeled and sized fields, and scripting to allow the user to continuously type the information by jumping from one field to the next one once the field is completed.
As a last note, don’t wait until the user fills the complete form to provide feedback, immediate validation is necessary to offer a positive user experience.