9 hours ago
Clickhouse really nailed this with the acquisition of peerdb. I used it with many terabyte databases and I essentially never thought about it. The only thing we really had to watch for was trying to replicate too much at once (because of the physical compute/io capacity of the postgres or clickhouse clusters).
an hour ago
It's interesting to watch how different companies that offer both Postgres and warehousing solution under 1 roof approach the same problem:
- ClickHouse focuses on traditional CDC (ClickPipes) and just make it blazingly fast
- Databricks leans on their unified storage architecture (LTAP) to avoid copying data (though you can argue there is still a copy in the cache)
- Snowflake uses a data mirroring CDC as extension so it runs directly on Postgres
I'm still waiting for a Postgres provider to just let me mirror data directly to Iceberg, so I can plug in my own stateless query engine.
4 minutes ago
Snowflake/Crunchydata comes close to doing that with the pglake extension.
There’s not a mirror function like what Snowflake offers directly but you can come close with a pgcron to upsert changes to the iceberg tables every so often.
You can also purge the table put to the iceberg version every so often too depending on your data needs. Then you can create a query unions the results of both.
28 minutes ago
> I'm still waiting for a Postgres provider to just let me mirror data directly to Iceberg, so I can plug in my own stateless query engine.
The issue that each of those providers above has recently adopted Postgres as a secondary product aimed at supporting their main product, an OLAP database or engine, so they don’t want you plugging in your own query engine.
I’d bet you’re likely to see this from a Postgres-specific provider first, like Supabase.
9 hours ago
This was basically Vertica's party trick for quite a long time to have a WOS and ROS formats for the same row and anti-caching between those two.
You could've built a similar system with dezebium and delta lake for quite some time but it would fail compactions, if you run it fast enough. I've seen Oracle GoldenGate 12c do this trick in 2014 or so, using Mysql as the cheap replica. But they are all fragile to schema updates in some direction.
The closest batteries-included equivalent to this is the Aurora -> Redshift bridge[1].
9 hours ago
Aurora zero etl was a nightmare for us. Almost any schema changes require a VACUUM FULL for it to continue functioning. On a few occasions, it just stopped running without an obvious explanation, requiring slow and lengthy back and forth threads with AWS support. If it worked as advertised, it would be great, but I can't recommend it for any serious production system.
8 hours ago
And this is, when it doesn't delete data randomly: https://github.com/trinodb/trino/issues/28885 (some enterprise open source was slop before AI even it seems)
8 hours ago
Although pg_lake is open source, worth noting that it heavily refers to but is missing CDC capabilities.
There's a bunch of comments/links to a closed https://github.com/snowflake-eng/sfpg-extension-pg_lake_repl...
2 hours ago
I'm interested in pg_lake so I wanted to check out your link, but it seems to be internal to snowflake?
2 hours ago
pg_lake is an open source Postgres extension based on work done at Crunchy Data prior to the acquisition by Snowflake - you can find the repo here [1] and a blog post with more context on the project here [2]
[1] https://github.com/Snowflake-Labs/pg_lake
[2] https://www.snowflake.com/en/blog/engineering/pg-lake-postgr...
28 minutes ago
Apologies, I could have introduced that better.
The article links https://github.com/Snowflake-Labs/pg_lake but if you go looking for CDC, it's not there, and all you end up with is links to the private/closed repo that I just linked, in various corners and spots. The point is that all the CDC stuff is in the repo we don't get access to, that isn't open source: https://github.com/snowflake-eng/sfpg-extension-pg_lake_repl...
9 hours ago
Snowflake is a really amazing product. It's been a delight using it the last few years.
3 hours ago
Seeing Postgres articles from Snowflake surprises me a lot though given how there's zero relation between Snowflake the product and Postgres itself
EDIT: I now see it's mainly to do with pushing data out of customer's postgres systems into snowflake
21 minutes ago
They acquired Crunchy Data and now have some of the most prominent Postgres developers working there.
5 hours ago
as much praise as some people give to it, I feel deeply uncomfortable with an idea of SaaS-only DB tech that you don't have an option to self host