What are the different types of key?

What is key and different types of key?

A key in DBMS is an attribute or a set of attributes that help to uniquely identify a tuple (or row) in a relation (or table). Keys are also used to establish relationships between the different tables and columns of a relational database. Individual values in a key are called key values.

What are the 5 types of primary key?

Primary Key.Candidate Key.Alternate Key.Super Key.Composite Key.Foreign Key.Unique Key.

What are the two types of keys?

Types of KeysSkeleton Key. Also known as a passkey, a skeleton key is a simple key with a cylindrical shaft and a single toothed end, which is used to open warded locks. ... Abloy Key. The Abloy key is used on disc tumbler locks. ... Dimple Key. ... Paracentric Key. ... Tubular Key. ... Keycard.

What are different types of keys used in DBMS?

Types of keys:Primary key. It is the first key used to identify one and only one instance of an entity uniquely. ... Candidate key. A candidate key is an attribute or set of attributes that can uniquely identify a tuple. ... Super Key. ... Foreign key. ... Alternate key. ... Composite key. ... Artificial key.