L&T Technology Services Software Engineer Interview Questions, Process, and Tips

DBMS keys are used to uniquely identify a record in a table. Primary, foreign, candidate, and super keys are some of the types.

• Primary key: uniquely identifies a record in a table

• Foreign key: links two tables together

• Candidate key: can be used as a primary key

• Super key: a set of attributes that can uniquely identify a record

• Composite key: a combination of two or more attributes used as a primary key