Page 93 - Computer Software Application TP - Volume 1
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COMPUTER SOFTWARE APPLICATION - CITS
Ensure that each table’s primary key constraint is enforced. MySQL automatically enforces primary key constraints,
preventing the insertion of duplicate keys.
3 ON DELETE/UPDATE Actions: Specify how the database reacts when data in the parent table is modified
(e.g., ON DELETE SET NULL sets foreign key to null, ON DELETE CASCADE deletes related rows).
4 CHECK Constraints: Define custom conditions for valid data (e.g., age must be positive).
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CITS : IT & ITES - Computer Software Application - Exercise 24
