CONSTRAINTS IN DATABASE | KEY CONSTRAINTS | DOMAIN CONSTRAINTS | REFERENTIAL INTEGRITY CONSTRAINTS скачать в хорошем качестве

CONSTRAINTS IN DATABASE | KEY CONSTRAINTS | DOMAIN CONSTRAINTS | REFERENTIAL INTEGRITY CONSTRAINTS

CONSTRAINTS IN DATABASE | CONSTRAINTS IN DBMS Constraints enforce limits to the data or type of data that can be inserted/updated/deleted from a table. Integrity constraints ensure that the data insertion, updating, and other processes have to be performed in such a way that data integrity is not affected. The whole purpose of constraints is to maintain the data integrity during an update/delete/insert into a table. There are three main integrity constraints − KEY CONSTRAINTS Identifies an entity within its entity set uniquely. DOMAIN CONSTRAINTS Validates set of values for an attribute. REFERENTIAL INTEGRITY CONSTRAINTS Specifies constraints between two tables. Primary Key    • KEYS IN DBMS | TYPES OF KEYS IN DBMS | CON...   ------------------------------------------------------------------------------------------------- Foreign Key    • KEYS IN DBMS | TYPES OF KEYS IN DBMS | CON...   ------------------------------------------------------------------------------------------------- Candidate Key    • KEYS IN DBMS | TYPES OF KEYS IN DBMS | CON...