DBMS-1

A DBMS is primarily used to:

• Design web applications

• Perform file compression

• Store and manage data efficiently

• All of the mentioned

The schema describes:

• Structure of the database

• Changes in the data of database

• Actual data in the database

• Backup copy of the data in the database

Which key is used to link two tables?

• Super Key

• Candidate Key

• Composite Key

• Foreign Key

• Private Key

To remove a table from the database, which command is used?

• REMOVE

• DELETE

• DROP

• CLEAR

• TRUNCATE

Which SQL keyword is used to prevent duplicate records in a query?

• DISTINCT

• UNIQUE

• NO DUPLICATE

• PRIMARY

• SINGLE

Which of the following is a DDL command?

• INSERT

• ALTER

• UPDATE

• SELECT

• DELETE

Which of the following is a DML command?

• CREATE

• GRANT

• COMMIT

• DELETE

• TRUNCATE

Which SQL command is used to change existing data in a table?

• UPDATE

• ALTER

• MODIFY

• CHANGE

• INSERT

Which command permanently saves all the changes made by the user?

• EXECUTE

• APPLY

• COMMIT

• SAVE

• FINAL

Which key can have NULL values in a relational table?

• Foreign Key

• Primary Key

• Candidate Key

• Super Key

• Composite Key