Using the option, you can change the state of a model back to where a particular feature or features weren`t yet created.

Rollback.                            

Explanation:

Rollback means to restore something to its previous state.In database rollback operation is used to restore the db to a previous state i.e. it will go back to its previous state.This command is used when you perform some incorrect operation on the database mistakenly which might result in affecting the consistency and integrity of data.Rollback option can be used to cancel or undo a single or a set of transactions to return the database to its previous state. It returns the database into the last committed state.Rollback can also be used in case of system or server crashes. For example a system crashes or a power failure, this option will roll back  or cancel the processes or transactions that were active during that system crash. So in this way the rollback option restores the database in a consistent state.For example, as we know that we can perform certain operations on data stored in a database such as insert, delete, update etc. So lets say we deleted some records of data from a database using DELETE operation but then we change our mind and use ROLLBACK command which will restore the database into its previous state and delete operation will not affect the records.

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