- Mobile-first: Realm is the first database built from the ground up to run directly inside phones, tablets and wearables.
- Simple: Data is directly exposed as objects and queryable by code, removing the need for ORM's riddled with performance & maintenance issues.
- Modern: Realm supports relationships, generics, and vectorization.
- Fast: Realm is faster than even raw SQLite on common operations, while maintaining an extremely rich feature set.
- Device Sync: Makes it simple to keep data in sync across users, devices, and your backend in real-time. Get started for free with a template application that includes a cloud backend and Sync.
Realm React Native and Node.js
The API reference is located at docs.mongodb.com/realm-sdks/js/latest/.
If you are using React Native, please also take a look the README for @realm/react, which provides React hooks to make working with Realm easier.
Template apps using Expo for React Native
- Need help with your code?: Look for previous questions on the #realm tag — or ask a new question. You can also check out our Community Forum where general questions about how to do something can be discussed.
- Have a bug to report? Open an issue. If possible, include the version of Realm, a full log, the Realm file, and a project that shows the issue.
- Have a feature request? Open an issue. Tell us what the feature should do, and why you want the feature.
See CONTRIBUTING.md for more details!
- Realm is not compatible with the Chrome Debugger. The following debugging methods are supported.
- Flipper has many similar features in relation to the Chrome Debugger. Please consider trying out our Hermes release to use the Hermes Debugger in Flipper and set breakpoints in your code.
- Safari also has a similar feature set, but requires some setup and only supports debugging in iOS.
- NOTE: For the above methods, it is not neccessary to enable
Debug with Chromein the Debug Menu.
- Version 10.21.0 accidently dropped support other Linux versions e.g., RHEL 7.
Building Realm JS
For instructions on building Realm JS yourself from source, see the building.md file.
Issues with debugging
Some users have reported the Chrome debugging being too slow to use after integrating Realm into their react-native project. This is due to the blocking nature of the RPC calls made through the Realm library. See https://github.com/realm/realm-js/issues/491 for more information. The best workaround is to use Safari instead, as a user has described here.
Moreover, we have a switch to Flipper in the works as part of our effort to support Hermes. It implies that we envision a near future where the Chrome debugging will be removed, and we currently don't invest much in its maintenance.
Asynchronously submits install information to Realm.
Why are we doing this? In short, because it helps us build a better product
for you. None of the data personally identifies you, your employer or your
app, but it will help us understand what language you use, what Node.js
versions you target, etc. Having this info will help prioritizing our time,
adding new features and deprecating old features. Collecting an anonymized
application path & anonymized machine identifier is the only way for us to
count actual usage of the other metrics accurately. If we don’t have a way to
deduplicate the info reported, it will be useless, as a single developer
npm install-ing the same app 10 times would report 10 times more than another
developer that only installs once, making the data all but useless.
No one likes sharing data unless it’s necessary, we get it, and we’ve
debated adding this for a long long time. If you truly, absolutely
feel compelled to not send this data back to Realm, then you can set an env
Currently the following information is reported:
- What version of Realm is being installed.
- The OS platform and version which is being used.
- Node.js version number.
- An anonymous machine identifier and hashed application path to aggregate the other information on.
Code of Conduct
Realm JS and Realm Core are published under the Apache License 2.0.
If you use Realm and are happy with it, all we ask is that you please consider sending out a tweet mentioning @realm to share your thoughts
And if you don't like it, please let us know what you would like improved, so we can fix it!