SELECT * Statement in View NOT Working
Introduction
View has some limitation. Using SELECT * within the view is not a good Idea. If we create view we must use the Columns name in the Select statement. We also recommended using to make materialized view (WITH SCHEMABINDING options).
Here in this article we are going to discuss about the adverse reaction of using SELECT * within a view.
Let's see a simple example to illustrate our point
Step – 1 [ Create a Base Table ]
IF OBJECT_ID(N'dbo.tbl_EMPLOYEE', N'U') IS NOT NULL
BEGIN
DROP TABLE [dbo].[tbl_EMPLOYEE];
END
GO
CREATE TABLE [dbo].[tbl_EMPLOYEE]
(
EMPID INT,
EMPNAME VARCHAR(50)
);
GO
Step – 2 [ Insert some Records in the base Table ]
INSERT INTO [dbo].[tbl_EMPLOYEE]
(EMPID, EMPNAME)
VALUES(1, 'Joydeep Das'),
(2, 'Sukamal Jana');
GO
Step – 3 [ Create A VIEW from this Base Table ]
IF OBJECT_ID(N'dbo.view_EMPLOYEE', N'V') IS NOT NULL
BEGIN
DROP VIEW [dbo].[view_EMPLOYEE];
END
GO
CREATE VIEW [dbo].[view_EMPLOYEE]
AS
SELECT * FROM [dbo].[tbl_EMPLOYEE];
GO
Step – 4 [ Run both Table and View ]
SELECT * FROM [dbo].[tbl_EMPLOYEE];
SELECT * FROM [dbo].[view_EMPLOYEE];
EMPID EMPNAME
----------- --------------------------------------------------
1 Joydeep Das
2 Sukamal Jana
EMPID EMPNAME
----------- --------------------------------------------------
1 Joydeep Das
2 Sukamal Jana
Step – 5 [ Add another columns to Base table ]
ALTER TABLE [dbo].[tbl_EMPLOYEE]
ADD [GRADE] CHAR(1);
GO
Step – 6 [ Update the New column with Data ]
UPDATE [dbo].[tbl_EMPLOYEE]
SET [GRADE] = 'A';
GO
Step – 7 [ Again Run both Table and View – Do we find any difference ]
SELECT * FROM [dbo].[tbl_EMPLOYEE];
SELECT * FROM [dbo].[view_EMPLOYEE];
EMPID EMPNAME GRADE
----------- --------------------- ----------
1 Joydeep Das A
2 Sukamal Jana A
EMPID EMPNAME
----------- ---------------------------------
1 Joydeep Das
2 Sukamal Jana
Step – 8 [ Run the sp_refreshview stored procedure ]
EXEC SP_REFRESHVIEW view_EMPLOYEE;
Step – 9 [ Again compare - Run both Table and View ]
SELECT * FROM [dbo].[tbl_EMPLOYEE];
SELECT * FROM [dbo].[view_EMPLOYEE];
EMPID EMPNAME GRADE
----------- ---------------------------------
1 Joydeep Das A
2 Sukamal Jana A
EMPID EMPNAME GRADE
----------- ----------------------------------
1 Joydeep Das A
2 Sukamal Jana A
Hope you like it.
