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Quick demo of Zero's new Background Queries More information in thread below 👇

Zero’s sync engine is query-based. Rather than specifying what to sync with rules or some separate system, you use queries. Right inside the client app, you do queries using a full sql-style language. You get filters, subqueries , limits, etc. Zero syncs the data for these queries to the client.

It’s important to realize because of this syncing, Zero isn’t really a cache. It’s a replica. It’s eagerly replicating a slice of your database - the slice covered by the queries you have open. So there's never stale data in Zero. When you close a query, we delete its rows so they don't go stale.

Of course that kind of sucks for the common case of doing a query, navigating, then pressing “back”. Ideally we want that to be fast. To address this Zero 0.17 adds background queries. You can add a ttl to a query and it will keep running and syncing in the background.

If you make a different query the data from the background query is used client-side to answer the new query instantly if possible. This all happens completely automatically. Just by adding the ttl flag. Learn more about Zero's query-based sync: zero.rocicorp.dev/docs/reading...