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. and any constraints we have enforced (primary key, foreign key, etc.). This example will rename our existing employees table to _employees_old. so far on the database can be done from R without ever opening SQLite Studio. 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. Therefore, you should perform the DROP TABLE statement with extra caution. You will not be able to undo or recover from this action. Notice that the DROP TABLE statement deletes the table from the database and the file on disk completely. ( employee_id INTEGER PRIMARY KEY AUTOINCREMENT, If a foreign key constraint violation occurs, SQLite issues an error message and will not drop the table. ( department_id INTEGER PRIMARY KEY AUTOINCREMENT, If you had created a foreign key in SQLite as follows:
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