Rollback Use this for all further examples Any changes to the data in the database are temporary. Changes to table structure are immediate. Turn off auto-commit Changes can be undone any time before you log off the Remove the foreman name database. from Polonia command restores all data to what it was when Rollback the transaction began. Rollback (verify) The MySQL Workbench is in mode by auto-commit default. All commands are committed as soon as they are entered correctly (no rollback) To have to turn allow rollbacks, you’ll off by clicking the Toggle auto-commit toolbar button (see more info below) mode Alternatively, you can type the command Set Autocommit = 0 If a command has been issued (see next Commit section), restores the data to what is was Rollback just after the Commit Commit Change the foreman name in Polonia to Smith, Steve makes all changes to the data during this Commit transaction permanent and ends the transaction Commit Rollback (verify Smith) When the toolbar button is Toggle auto-commit mode OFF, the MySQL Workbench provides Rollback and Commit buttons that work exactly the same as the MySQL commands. I use these buttons to determine if auto-commit is off. If this button is active, auto-commit if off button appearance for on/off is not that different). Deleting Rows From tblFebTrips, delete Delete From TABLENAME all trips to Miami (optional) Where condition If no condition, deletes all records. Display the number of trips If primary key not part of Where clause, need to turn to each city (FebTrips) off in MySQL Workbench (see above) “Safe Update” Rollback (and verify)
Rollback Any changes to the data in the database are temporary. Changes to table structure are immediate. Changes can be undone any time before you log off the database. Rollback command restores all data to what it was when the transaction began. The MySQL Workbench is in auto-commit mode by default. All commands are committed as soon as they are entered correctly (no rollback) To allow rollbacks, you’ll have to turn off by clicking the Toggle auto-commit mode toolbar button (see more info below) Alternatively, you can type the command Set Autocommit = 0 If a Commit command has been issued (see next section), Rollback restores the data to what is was just after the Commit Use this for all further examples Turn off auto-commit Remove the foreman name from Polonia Rollback (verify) Commit Commit makes all changes to the data during this transaction permanent and ends the transaction Change the foreman name in Polonia to Smith, Steve Commit Rollback (verify Smith) When the Toggle auto-commit mode toolbar button is OFF, the MySQL Workbench provides Rollback and Commit buttons that work exactly the same as the MySQL commands. I use these buttons to determine if auto-commit is off. If this button is active, auto-commit if off button appearance for on/off is not that different). Deleting Rows Delete From TABLENAME Where condition (optional) If no condition, deletes all records. If primary key not part of Where clause, need to turn off “Safe Update” in MySQL Workbench (see above) From tblFebTrips, delete all trips to Miami Display the number of trips to each city (FebTrips) Rollback (and verify)
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