Views

Virtual tables that can be manipulated in the same way as tables from the CREATE TABLE statement.

 
V1: 		 CREATE VIEW 		 		 WORKS_ON1

		 AS 		 SELECT 		 FNAME,LNAME,PNAME,HOURS

		 		 FROM 		 EMPLOYEE,PROJECT,WORKS_ON

		 		 WHERE 		 SSN=ESSN AND PNO=PNUMBER;

 
V2: 		 CREATE VIEW 		 		 DEPT_INFO (DEPT_NAME,NO_OF_EMPS,
TOTAL_SAL)

		 AS 		 SELECT 		 DNAME,COUNT(*),SUM(SALARY)

		 		 FROM 		 DEPARTMENT,EMPLOYEE

		 		 WHERE 		 DNUMBER=DNO

		 		 GROUP BY 		 DNAME;

• Querying Views
• Dropping Views
• Updating Views
• Corresponding Base Relations
• View Updates Might Not Make Sense