SQL · Schema and constraints

foreign key

Enforces a relationship to another table and can cascade changes.

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Syntax

references other(id) on delete cascade

Example

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PRAGMA foreign_keys = ON;
CREATE TABLE courses (id INTEGER PRIMARY KEY);
CREATE TABLE lessons (
  id INTEGER PRIMARY KEY,
  course_id INTEGER REFERENCES courses(id) ON DELETE CASCADE
);
SELECT name FROM sqlite_master WHERE name = 'lessons';

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foreign key

Example

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