![]() ![]() PRAGMA foreignkeys ON Disable foreign key constraints. So if your AUTHORS table has an autoincrementing integer primary key, your TITLES.AuthorID column would simply be an integer with no autoincrement capability. In the SQLite database, foreign key constraints are disabled by default, so foreign key constraints must be enabled for eachdatabase connection. A column with a foreign key constraint is not typically an autoincrementing value but refers to a (pre-existing) key value in another table. ![]() This workaround allows you to drop a foreign key from the employees table without losing the data in the table. A foreign key uses to enforce the relationships between two or more tables in SQLite database. 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. INSERT INTO employees SELECT * FROM _employees_old ![]() 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. In this example, we've created a primary key on the departments table that consists of only one field - the department_id field. ( employee_id INTEGER PRIMARY KEY AUTOINCREMENT, ( department_id INTEGER PRIMARY KEY AUTOINCREMENT, If you had created a foreign key in SQLite as follows: ![]()
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