Support for set transaction snapshot?

Does cockroachdb support this ?
It’s explained here on the postgresql side: https://thebuild.com/blog/2019/02/11/whats-up-with-set-transaction-snapshot/

CockroachDB supports a feature that’s very close and can be used to solve the same problems: AS OF SYSTEM TIME.

See here: https://www.cockroachlabs.com/docs/stable/as-of-system-time.html

So if the connection is left open, the data isn’t deleted (like normal mvcc).
And same timestamp in nanoseconds can be used by multiple connections and they see the same data ?

I don’t understand your comment about data not being deleted. Old versions in CockroachDB will be automatically garbage collected after a configurable period, which is 25 hours by default.

The same timestamp can be used by multiple transactions, yes.

In postgresql, the db can’t vacuum when you leave a transaction open. Is it the same in cockroachdb or the data is deleted regardless ?

An abandoned transaction will get aborted automatically after a delay (I think it’s 10 minutes). Then after that its data will be garbage collected (by default 25 hours).

It won’t be abandoned, it will be reading.

CockroachDB does not support long-running transactions containing write statements.

If your transaction is read-only, there won’t be any changes to vacuum.

If the transaction contains writes, and it does not commit with some delay (I think 10 minutes, maybe more), CockroachDB will force-abort it. Then later (25 hours) it will get garbage collected.