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Comment by daliwali | Hacker News Reader

CockroachDB looks like a great alternative to PostgreSQL, congrats to the team for doing so much in such a short time. The wire protocol is compatible with Postgres, which allows re-using battle-tested Postgres clients. However it's a non-starter for my use case since it lacks array columns, which Postgres supports [0]. I also make use of fairly recent SQL features introduced in Postgres 9.4, but I'm not sure if there are major issues with compatibility.

[0] https://github.com/cockroachdb/cockroach/issues/2115

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I'm an engineer on the SQL team at CockroachDB. We're very aware of our missing support for array column types - and in fact beginning to add support for arrays is one of my team's priorities for the next release cycle.

What kind of other recent SQL features introduced in Postgres 9.4 do you use? Postgres has a ton of features, as I'm sure you're aware, and while we strive for wire compatibility with Postgres it's not a goal of ours to implement support for every Postgres feature out there.

what's the story for change data capture with CockroachDB? Postgres 9.4 added logical replication, which is incredibly useful for this use case.

Also, we use JSONB fairly extensively -- I see the tracking issue here https://github.com/cockroachdb/cockroach/issues/2969 but no movement.

Regarding change data capture, please see Arjun's answer: https://news.ycombinator.com/item?id=14309173

Make sure to take a look at Debezium: http://debezium.io/

It's a really solid CDC framework which has connectors for PostgreSQL, MySQL and MongoDB.

I double checked my codebase and it looks like it's just JSONB, which CockroachDB also doesn't support [0]. Sorry to bother about missing features, but there are really some things that prevent a smooth transition from Postgres.

[0] https://github.com/cockroachdb/cockroach/issues/2969

Yep, JSONB is on our roadmap as well, although it won't come before array column type support. Thanks for the feedback - I'd personally love to see migrations from PostgreSQL to CockroachDB become seamless for more complex use cases as we continue development.

It occurred to me to migrate Odoo ERP to CockroachDB, scaling up the DB is one of our biggest challenges with some of our clients.

However Odoo leans heavily on Postgres, migration would be a lot of work I imagine. The first snag I've hit with CockroachDB is the lack of 'CREATE SEQUENCE'.

Plus, Odoo uses REPEATABLE READ + a hand-rolled system of locks for consistency, I'm not sure how that would play out with CockroachDB. In my experience some of the performance issues come more from long lived locks in the app than from sheer DB performance.

JSON/JSONB datatypes, listen/notify, spatial extensions.

JSON/JSONB will come after array support. As far as I know, we don't have any concrete plans at this time to support listen/notify or spatial datatypes.

Postgres' network types [0] are very useful, especially when you use the << and >> operators to query for addresses contained in a subnet.

[0] https://www.postgresql.org/docs/9.5/static/datatype-net-type...

I'm basically here to ask a similar question, whether this is aimed as an modern alternative to Postgresql, since they don't clearly state this on the OP news announcement.

To me, at least for now, it seems more like a SQL enabled etcd or similar. They aren't currently claiming performance numbers that make it sound suitable for general purpose relational database scenarios. A SQL aware etcd like thing has a lot of appeal though, and I assume the performance work is coming.

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