Data security is not optional in today's business environment. High-visibility hacking and fraud, Sarbanes-Oxley, HIPAA regulations, and the Patriot Act all reinforce the need to present the right data to the right users and prevent the wrong ones from gaining access. Typically, "row level security" is one requirement: to allow or permit access to particular users based on data in the row. SQL Server does not provide built-in row level security.
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