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Yes this is correct. The performance benefit comes from doing all this stuff on the CPU instead of using disc-io. Also the internal binary decision diagram of EventReduced is optimized in a way to run less logic then a query would do. This makes it even faster then running the query again with an in-memory database.

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And the main cost of this (questionable IMO) benefit is losing consistency, which is losing any change to DB not coming from the calling app. You haven't mentioned this cost anywhere.

The writes are not tunneled somehow through this algorithm. You still use the database like your normally would do. So the consistency is not affected.

Also this is an open source project, not something I want to sell you. Feel free to make a PR/issue with any open topics that are not mentioned in the docs.

>The writes are not tunneled somehow through this algorithm

Then I fail to understand how it works. How Event-Reduce becomes aware of these "write events"?

>this is an open source project, not something I want to sell you

You made it open source so others can use it, right? They better be making an informed decision whether your solution suits their needs.

You have to provide the events by yourself. See EventReduce as a simple function that can do oldResults+Event=newResults.

And yes, you should always do testings before you use open source stuff. There is no warranty use it on your own risk.

OK, so you don't "tunnel writes through" EventReduce, you "tee" them to EventReduce.

Anyway, to maintain consistency, you have to limit yourself to one process of your app. No sharding, load-balancing etc. This is significant limitation, and it's not obvious. I encourage you to mention it in README.md.

I encourage you to read the readme and check out the demo. EventReduce is nothing magically drills out your database and affects the consistency of your write-accesses.

It is a simple algorithm that is implemented as a function with two inputs and one output.

> How Event-Reduce becomes aware of these "write events"?

Some DBs expose an event stream, for example, PG:

https://www.postgresql.org/docs/current/logicaldecoding-expl...

> For the different implementations in common browser databases, we can observe an up to 12 times faster displaying of new query results after a write occurred.

Is this intended to be an optimisation on top of localStorage and so on? If so, at least you don't have to worry about multiple writers.

localStorage is no database, check out the demo page.

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