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What are different types of constraints? describe in brief?

22nd Sep 2016, 5:25 AM
neha
neha - avatar
2 Answers
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UNIQUE - Requires a unique value, no duplicate records NOT NULL - Requires a value, can't be blank PRIMARY KEY - Designates a table's Primary Key
27th Sep 2016, 1:18 AM
Chris G
Chris G - avatar
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I agree: UNIQUE - Requires a unique unduplicated record NOT NULL - Requires a value, can't be left empty, forces an entry to be present PRIMARY KEY - Only accepts a unique entry in the field where this is present
4th Oct 2016, 3:13 PM
MrTurner