How Do I Enable Foreign Key Constraints in SQLite3?

SQLite3 and Foreign Key Constraints

Despite its extensive capabilities, SQLite3 initially faces a specific constraint when it comes to foreign key enforcement. While foreign keys are crucial for maintaining data integrity, SQLite3 requires an additional step to enable them.

Specifically, when working with SQLite3 versions prior to 4.x, the following query must be executed every time a connection is established:

PRAGMA foreign_keys = ON;

By default, SQLite3 inherits its behavior from its predecessor, SQLite 2.x, which did not support foreign key constraints. To maintain backward compatibility, SQLite3 requires the explicit activation of foreign keys through the PRAGMA query.

In contrast, SQLite4.x takes a different approach, automatically enabling foreign key constraints by default. This eliminates the need for the additional query, streamlining the workflow and ensuring data integrity without manual intervention.

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