An example to perform as:
CREATE A PROCEDURE dbo.MyProcedure WITH EXECUTE AS OWNER
In this case, you impersonate the owner of the called module. You can also impersonate SELF, or the user who creates or modifies the OR ... imperonate CALLER module, which allows the module to accept the permissions of the current user, OR ... impersonate the OWNER who will accept the permission of the owner of the procedure called OR ... impersonate " user_name ", which pretends to be a specific user or ... impersonate 'login_name' to impersonate a specific login.
Setting permissions on objects such as stored procedures can be done using "GRANT EXECUTE ON. To," however, you can also provide security rights both at the login level and at the user level. You will want to define and grant ONLY the necessary rights for objects that require access (for example, execution). Consider using the "EXECUTE AS" function, which allows you to impersonate another user to verify the permissions required to execute the code without having to grant all the necessary rights to all the main objects (for example, tables). EXECUTE AS can be added to stored processes, functions, triggers, etc.
In TIME BRIDGE, you will need to grant EXECUTE rights to the stored processes, and then the rights will be granted to all objects specified in the stored procedure. Thus, you do not need to provide implicit rights (for example: to update data or to call additional procedures). Own chain processes this for you. This is especially useful for dynamic sql or if you need to create advanced security tasks such as CREATE TABLE. EXECUTE AS is a convenient tool for reviewing them.
This example can help clarify all of this:
Create a user named NoPrivUser with public access to the database (e.g. dbadb)
USE [wizard] GO CREATE LOGIN [NoPrivUser] WITH PASSWORD = N'ABC5% ', DEFAULT_DATABASE = [dbadb], CHECK_EXPIRATION = ON, CHECK_POLICY = ON GO GO USE [DBAdb] GO NORTH CLEAR]
NOTE. THE CREATOR OR OWNER OF THIS PROCEDURE IS REQUIRED TO CREATE TABLE RIGHTS in the target database.
use DBAdb to go CREATE PROCEDURE dbo.MyProcedure WITH EXECUTE AS OWNER IN VIEW IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID (N '[dbo] .MyTable') And enter (N'U ')) CREATE TLE (PKid int, column1 char (10)) INSERT MYTable VALUES (1, "ABCDEF")
GO
GRANT EXEC ON dbo.MyProcedure TO NoPrivUser; GO
- Now log in to your database server as NoPrivUser and run the following.
use dbadb to go
EXEC dbo.MyProcedure
(1 row (s) affected)
Now try selecting from a new table during login as NoPrivuser.
You will receive the following:
select * from mytable go
Msg 229, Level 14, State 5, Line 1 SELECT permission was denied for the object "MyTable", database "DBAdb", schema "dbo".
This was expected since you only started the procedure in the context of the Owner’s security when you logged in as NoPrivUser.
NoPrivUser like no rights to actually read the table. Just to execute a procedure that creates and inserts rows.
With the EXECUTE AS clause, the stored procedure is launched in the context of the owner of the object. This code successfully creates dbo.MyTable, and the rows are successfully inserted. In this example, the user "NoPrivUser" does not have absolute rights to modify the table or to read or modify any data in this table.
It accepts only the rights necessary to complete this specific task, encoded in the context of this procedure.
This method of creating stored procedures that can perform tasks that require increased security rights without the permanent assignment of these rights is very useful.