We've spent a great number of years building exceptionally diverse databases. A common request from customers is to provide support and manuals. This week, we were reviewing one new database and I noted that as a company we are finally starting to standardize our database front ends.
In particular, we have started thinking of long term support requirements, and users who may not have been involved in the design and implementation process coming into an existing database with no understanding of the requirements. Many companies build their databases using internal employees as the architects, and meetings with stake holders to define the fields and requirements - leading to complete loss of knowledge when those employees move on to other jobs or companies.
One solution we now do is simple - set the Control Tip Text on every field, so when a user hovers their mouse over a field they get a useful popup beside it with a help suggestion (ex. Enter the employee's date of birth using the format mm/dd/yy). This guides the user through required formats, and helps prevent bad data in your database.
You can build a database with many features and fancy code, but you can't always predict what new employees will interpret as required inputs. So use Control Tip Text to prevent errors and simple help desk phone calls!