What is a constraint?
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It is a standard method to enforce information integrity
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It is a standard method to manipulate data in databases
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They are policies to enforce security access to database
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Are method that allow users to authenticate
Reveal answer
Fill a bubble to check yourself
A
Correct answer
Explanation
A constraint is a rule enforced at the database level to maintain data integrity and ensure information accuracy. Constraints prevent invalid data entry (like NOT NULL prevents nulls, UNIQUE prevents duplicates, CHECK validates values). Option B is incorrect because constraints don't manipulate data - that's what DML statements do. Option C confuses constraints with security policies. Option D confuses constraints with authentication mechanisms.