![]() ![]() This workaround allows you to drop a foreign key from the employees table without losing the data in the table. Then it will insert all of the data from the _employees_old table into the employees table. Then it will create the new employees table without a foreign key. This example will rename our existing employees table to _employees_old. It enforces referential integrity within SQLite database. INSERT INTO employees SELECT * FROM _employees_old SQLite Foreign Key is used to specify that values in one table also appear in another table. If we then wanted to drop the foreign key called fk_departments, we could execute the following command: PRAGMA foreign_keys=off ĪLTER TABLE employees RENAME TO _employees_old Then we've created a foreign key called fk_departments on the employees table that references the departments table based on the department_id field. Description Once a foreign key has been created, you may find that you wish to drop the foreign key from the table. In this example, we've created a primary key on the departments table that consists of only one field - the department_id field. This SQLite tutorial explains how to drop a foreign key in SQLite with syntax and examples. ( employee_id INTEGER PRIMARY KEY AUTOINCREMENT, ( department_id INTEGER PRIMARY KEY AUTOINCREMENT, ![]() If you had created a foreign key in SQLite as follows: In this tutorial, you will learn- SQLite Constraints SQLite Primary Key Not null constraint DEFAULT Constraint UNIQUE constraint CHECK constraint SQLite Foreign Key SQLite Constraints Column constraints enforce constraints and rules to the values inserted on a column in order to validate the inserted data.
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