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This is so cool!

From the blog post it says read-only replicas are created close to users and kept up to date with the latest data.

- How should I think about this in terms of CAP? If there's a write and I query a replica what happens?

- How are writes handled? Do they go to a single location or are they handled by various locations?

I'm excited to try this. It's so cool to see databases being distributed "on CDNs" for lack of a better term.

I think they're replicated asynchronously, so reading directly from the replica may return old data. That's why they've added the ability to deploy special workers that "live" closer to the primary:

> Embedded compute

> But we're going further. With D1, it will be possible to define a chunk of your Worker code that runs directly next to the database, giving you total control and maximum performance — each request first hits your Worker near your users, but depending on the operation, can hand off to another Worker deployed alongside a replica or your primary D1 instance to complete its work.

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