What Is a Transaction?

A transaction is a single operation or set of operations that succeed or fail together as a whole, thereby ensuring consistency of data should unforeseen circumstances arise. A classic scenario is the typical financial transaction. For example, let’s say you buy a car. The single transaction of buying a car consists of three distinct operations:

  1. You select a car.

  2. You pay for it.

  3. You drive the car off the lot.

Skipping any of these steps could cause major angst to one or more of the parties involved. This is a simple example of a set of steps that must always occur together in a consistent manner.

Transactions allow you to ensure consistency in your data through four basic principles. These principles provide a set of rules that ...

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