cainophile
revori
| cainophile | revori | |
|---|---|---|
| 2 | 1 | |
| 234 | 10 | |
| 1.3% | - | |
| 1.7 | 0.0 | |
| 2 months ago | over 9 years ago | |
| Elixir | Java | |
| Apache License 2.0 | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
cainophile
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How to Listen to Database Changes Using Postgres Triggers in Elixir
If you want to listen to database changes in Elixir you can also get really good stuff done by using Cainophile (https://github.com/cainophile/cainophile). Same mechanism. I don't know the details of Debezium so I can't say if you are leaving fantastic things on the table. But I've had good fun with Cainophile. For example I've used it in my videos on Electric SQL to react to changes in a Postgres database. It matches nicely with realtime-ish UI via LiveView. So meshes really good with the current Elixir stack.
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Ask HN: Is there a way to subscribe to an SQL query for changes?
https://github.com/cainophile/cainophile
I happened to do a similar thing but I adapted cainophile into an Elixir “OffBroadway” producer:
revori
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Ask HN: Is there a way to subscribe to an SQL query for changes?
I've implemented a RDBMS that supports this [1]. It handles joins, views (which are automatically materialized and incrementally updated), etc. It's memory only, and it doesn't support exotic stuff like recursive CTEs, but it does exactly what you're asking for. We used it in production successfully for frequently-updated real time data at the company where I used to work.
Notably, it uses persistent search trees such that each revision shares structure with the previous one, which makes diffing two closely-related revisions extremely efficient (just skip over any shared structure). Subscribers just receive a stream of diffs, with backpressure handled automatically by skipping over intermediate revisions. See [2] for a more detailed summary.
It also exposes revisions as first-class objects, which allows you to tag and diff them. Specifically, you can run arbitrary queries on both revisions and diffs. See [3] for examples.
It's no longer maintained, unfortunately. Someday I may revive it, perhaps adding support for spilling data that won't fit in memory to log-structured merge trees. I'd also rewrite it in a language like Rust, which will help flatten some of the more pointer-heavy data structures and reduce tail latencies. If anyone is interested in seeing that happen or helping out, let me know.
I'm really surprised this still isn't supported in mainstream DBMSes. The MVCC model in PostgreSQL seems particularly well suited to it.
[1]: https://github.com/ReadyTalk/revori
What are some alternatives?
noria - Fast web applications through dynamic, partially-stateful dataflow
rethinkdb_rebirth - The open-source database for the realtime web.
supavisor - A cloud-native, multi-tenant Postgres connection pooler.
pg-live-select - Live Updating PostgreSQL SELECT statements
timely-dataflow - A modular implementation of timely dataflow in Rust
PipelineDB - High-performance time-series aggregation for PostgreSQL
flow - 🌊 Continuously synchronize the systems where your data lives, to the systems where you _want_ it to live, with Estuary Flow. 🌊