Range checking provides a particularly powerful set of diagnostics. It monitors the execution of methods while the compiled database is running.

Range checking does not display messages during compilation. Its messages can appear only while you are using the compiled database. Range checking is very useful because there are certain types of problems that can be detected only while the database executes (string size mismatch for example).

How and When to Use Range Checking
When you request range checking, certain areas of your compiled application may become slower than they are without this option. Therefore, range checking should not be requested for the final compilation of a finished database.

Range checking should be used as an additional phase in the process of developing and debugging your databases. We assume that you will run a final compilation without range checking. The compiler’s most obvious purpose is to speed up databases. An equally important goal is to help you make your applications reliable. We therefore recommend that you consider a development phase that includes range checking.