Understanding data integrity

Data integrity refers to the consistency and accuracy of the data. It is typically enforced by the procedures and guidelines in the database design phase. In RDMS, keys enforce data integrity. A key is user-defined and forces values in a table to conform to a specified standard. This standard will allow only certain kinds of values to be in the database.

Types of integrity

Data integrity refers to the consistency and accuracy of data and table relationships. The following table lists the types of integrity you can use:

Entity integrity	Referential integrity	Domain integrity
Unique constraint	Foreign key	Check constraint
Not null constraint		Default constraint
Primary key...