Mastering Flask Web Development - Second Edition

Data integrity

Integrity is also one of the biggest selling points of RDBMSes. RDBMSes have several methods in place to ensure that the data entered into a database will not only be correct, but that data loss will be practically nonexistent. These methods combine to form what is known as ACID (short for atomicity, consistency, isolation, and durability). ACID is a set of rules for transactions that guarantee that the transaction is handled safely.

The principle of atomicity requires that each transaction is all or nothing. If one part of the transaction fails, the entire transaction fails. This is much like the following quote from The Zen of Python:

"Errors should never pass silently. Unless explicitly silenced."

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