Integrity Constraints

Integrity constraints or consistency rules must be applies to database so that the correct data can be entered into the database without any duplication or redundancy. The constraints may be applied to data item within a single record or may be applied to relationship between records.It is one of the most important advantages of database management system.

Most of the DBMSs provide the facility for applying the integrity constraints. The database designer identifies integrity constraints during database design. The application programmer can also identifies the integrity constraints in the program code during developing the application program. The integrity constraints are automatically checked at the time of data entry or when the record is updated with in file.