sql – What is the difference between a stored procedure and a view?

sql – What is the difference between a stored procedure and a view?

A view represents a virtual table. You can join multiple tables in a view and use the view to present the data as if the data were coming from a single table.

A stored procedure uses parameters to do a function… whether it is updating and inserting data, or returning single values or data sets.

Creating Views and Stored Procedures – has some information from Microsoft as to when and why to use each.

Say I have two tables:

  • tbl_user, with columns: user_id, user_name, user_pw
  • tbl_profile, with columns: profile_id, user_id, profile_description

So, if I find myself querying from those tables A LOT… instead of doing the join in EVERY piece of SQL, I would define a view like:

CREATE VIEW vw_user_profile
AS
  SELECT A.user_id, B.profile_description
  FROM tbl_user A LEFT JOIN tbl_profile B ON A.user_id = b.user_id
GO

Thus, if I want to query profile_description by user_id in the future, all I have to do is:

SELECT profile_description FROM vw_user_profile WHERE user_id = @ID

That code could be used in a stored procedure like:

CREATE PROCEDURE dbo.getDesc
    @ID int
AS
BEGIN
    SELECT profile_description FROM vw_user_profile WHERE user_id = @ID
END
GO

So, later on, I can call:

dbo.getDesc 25

and I will get the description for user_id 25, where the 25 is your parameter.

There is obviously a lot more detail, this is just the basic idea.

Plenty of info available here

Here is a good summary:

A Stored Procedure:

  • Accepts parameters
  • Can NOT be used as building block in a larger query
  • Can contain several statements, loops, IF ELSE, etc.
  • Can perform modifications to one or several tables
  • Can NOT be used as the target of an INSERT, UPDATE or DELETE
    statement.

A View:

  • Does NOT accept parameters
  • Can be used as building block in a larger query
  • Can contain only one single SELECT query
  • Can NOT perform modifications to any table
  • But can (sometimes) be used as the target of an INSERT, UPDATE or
    DELETE statement.

sql – What is the difference between a stored procedure and a view?

First you need to understand, that both are different things. Stored Procedures are best used for INSERT-UPDATE-DELETE statements. Whereas Views are used for SELECT statements. You should use both of them.

In views you cannot alter the data. Some databases have updatable Views where you can use INSERT-UPDATE-DELETE on Views.

Leave a Reply

Your email address will not be published.