A system and method for preventing user-input text strings of illegal lengths from being submitted to a database where, for each character in the string, a character length is determined in quantities of digital units of storage according to an encoding schema, the character lengths are accumulated into a total string length, also measured in digital units of storage, and the total string length is compared to one or more database input field requirements such as non-null and maximum length specifications. If a limit is not met, the system and method are suitable disposed in a manner to block or prevent submission of the user-input string to the database. The invention can alternatively be realized as a plug-in for database front-end application programs, as a stand-alone web services provider, or as a plug-in for a client-side database access program such as a web browser.