What is Database Security?

Generally the terms "security" and "integrity" are considered to be same, but these two concepts are quite distinct. Security refers to the protection of data against unauthorized disclosure, alteration or destruction; integrity refers to the accuracy or validity of data. In other words:

• Security involves ensuring that users are allowed to do the things they are trying to do;
• Integrity involves ensuring that the things they are trying to do are correct.

Now the Question arises that why do we need Security?

The very obvious reason for the security is to prevent the misuse of the database by intentional (malicious) and accidental causes.

• Accidental loss of data consistency may result from
• Crashes during transaction processing;
• Anomalies caused by concurrent access to the database;
• Anomalies caused by the distribution of data over several computers;
• Logical errors that violate the assumption that transaction preserve the database consistency constraints.

The loss of data due to malicious access to data results from following:

• Unauthorized reading of data (theft of information);
• Unauthorized modification of data
• Unauthorized destruction of data.