We discuss the problems caused by concurrently executing transactions
in Section 14.5. The isolation property of a transaction ensures that the concurrent
execution of transactions results in a system state that is equivalent
to a state that could have been obtained had these transactions executed one
at a time in some order.We shall discuss the principles of isolation further in
Section 14.6. Ensuring the isolation property is the responsibility of a component
of the database system called the concurrency-control system, which
we discuss later, in Chapter 15.