Modifying the Database

1. QBE has facilities for modifying the database.

Deletion

1. We simply use D. instead of the P. operator. Whole tuples may be deleted, or only some columns.

2. Delete all of Smith's account records:

   

3. Delete the branch-city value for the SFU branch:

   

4. Delete all loans with loan numbers between 1300 and 1500:

   

   

5. Delete all accounts at branches located in Burnaby:

   

   

• Insertion
• Updates