COMPUTER SCIENCE AND ENGINEERING
DATABASE MANAGEMENT SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following is not fully supported by all commercially available systems, but supports if religiously?
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Entity integrity
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Referential integrity
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Relational algebra
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Relational calculus
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Explanation:
Detailed explanation-1: -1. Which of the following is not an integrity constraint? Explanation: Identical is not an allowed integrity constraint in SQL. Not null prevents null values and unique only allows unique values to be entered.
Detailed explanation-2: -Three types of rules can be attached to each referential constraint: an INSERT rule, an UPDATE rule, and a DELETE rule.
Detailed explanation-3: -A foreign key constraint (also referred to as a referential constraint or a referential integrity constraint) is a logical rule about values in one or more columns in one or more tables.
There is 1 question to complete.