# The User Write Lock: an Alternative to Transactions for Google App Engine

DevFeed: [The User Write Lock: an Alternative to Transactions for Google App Engine](<https://devfeed.tech/articles/the-user-write-lock-an-alternative-to-transactions-for-google-app-engine-27418.md>)

Original publisher: [Read original article](<http://engineering.khanacademy.org/posts/user-write-lock.htm>)

Author: Khan Academy

Published: 2016-06-20T22:00:00Z

Content type: tutorial

Language: en

Sources: [Khan Academy](<https://devfeed.tech/sources/khan-academy.md>)

Topics: [Transactions](<https://devfeed.tech/topics/transactions.md>), [Databases](<https://devfeed.tech/topics/databases.md>), [Google](<https://devfeed.tech/topics/google.md>)

Tags: [caching](<https://devfeed.tech/tags/caching.md>), [databases](<https://devfeed.tech/tags/databases.md>), [engineering](<https://devfeed.tech/tags/engineering.md>), [google](<https://devfeed.tech/tags/google.md>), [infrastructure](<https://devfeed.tech/tags/infrastructure.md>), [news](<https://devfeed.tech/tags/news.md>), [processes](<https://devfeed.tech/tags/processes.md>), [retry](<https://devfeed.tech/tags/retry.md>), [transactions](<https://devfeed.tech/tags/transactions.md>)

## AI overview

This developer article explains how transactions in Google App Engine's datastore provide atomicity for single-entity and multi-entity writes, but can introduce frozen datastore state, retries, idempotence requirements, and restrictions on datastore queries. It presents the User Write Lock as an alternative, although the supplied text ends before describing that alternative.

## Source excerpt

By Craig Silverstein Transactions are the standard method in Google App Engine's datastore -- as in many databases ... Read more