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FOREIGN KEY Constraint

The FOREIGN KEY constraint is used to link two tables. It ensures that the value in a column corresponds to a value in another table's primary key or unique column.

Example: Creating a Table with FOREIGN KEY

CREATE TABLE Contributions (
    ContributionID INT PRIMARY KEY,
    FighterID INT,
    Amount DECIMAL(10, 2),
    FOREIGN KEY (FighterID) REFERENCES FreedomFighters(FighterID)
);

Explanation: The FighterID in the Contributions table is a foreign key referencing the FighterID in the FreedomFighters table, establishing a relationship between the tables.

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