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Update Operations and Dealing with Constraint Violations
There are three basic operations to be executes on relations:
The INSERT Operation:
The insert operation permits us to insert a new tuple in a relation. When we try to insert a new record, then any of the following four types of constraints can be violated:
• Entity Integrity constraint: If the primary key attribute value of new tuple t is given as null.
What is a super key? A super key is a set of one or more attributes that collectively permits us to recognize uniquely an entity in the entity set.
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What are the function of DBA?
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