Database security....

The most impotant database security concepts are authentication and authorization.

Authentication is the process of validating user credentials to prevent unauthorized users from using a system.Authentication is the most commonly enforced by requiring the user to enter username and password.This information evaluated by the system to determine whether the user is allowed to access the system.This process can be strengthened by using encryption.

Authorization is the process that is applied after the identity of a user is authenticated.During this process,the system determines what resources the purticular user can use.In other words structuraland system catalog information about a purticular entity is now available only to principles that have permission to aaccess that entity

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Please refer following links
http://msdn.microsoft.com/en-us/library/aa291801%28v=vs.71%29.aspx
http://msdn.microsoft.com/en-us/library/bb510589.aspx

Rajesh Patel
R.P.A Developer | Developer Trainer | Clean Code Evangelist

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