[From MySQL AB
The IT crown jewels of any organization lies in their database infrastructure. Obviously, well-designed front end applications play a leading role when it comes to ensuring that critical information is captured or reviewed, but the buck stops at the database when it comes to data retention and protection.
Because such things are the database's responsibility, it is important that the underlying engine act in ways that preserve the integrity and validity of the data. This means the RDBMS should stand guard and deny entry of any and all invalid data through the welcome gates of the actual database.
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