> ## Documentation Index
> Fetch the complete documentation index at: https://developer.vetcove.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Reading & writing data

To improve performance and scalability, our system uses **follower databases** for all API read operations. These followers replicate data from the primary database but operate with eventual consistency, meaning there may be a short delay before changes made to the primary database propagate to the followers. As a result, there is a possibility that a recently created or updated entity may not be immediately available in a follower. To handle this, when querying for an individual entity, our application first attempts to read from a follower. If the follower returns a `404 Not Found` error, we fall back to the primary database to check for the entity before concluding that it does not exist.

Developers should be mindful of this behavior, especially when building user-facing features that require immediate consistency after writes. In cases where strong consistency is needed—such as confirming a newly created record or ensuring a recent update is reflected—developers should use the returned object from the API response.

If you have a unique use case that requires strong consistency, please contact us at [dev-support@vetcove.com](mailto:dev-support@vetcove.com) for further assistance.