Before we go beyond the basics of transactions, let’s review some terminology that is commonly used when talking about transactions:.
Beginning a transaction. Specifying that all subsequent operations that occur after a transaction begins are assumed to lie within the transaction.
Rolling back a transaction. Undoing operations that have occurred since a transaction began, thus restoring the affected data to its original state. This is done in the event of failure.
Committing a transaction. Making permanent all operations that have occurred since a transaction began. A transaction is committed in the event of success.
Dirty read. The operation of reading data that is yet to be committed. This occurs, for example, when transaction ...