Can crdb support read-committed isolation?

Will crdb support RC isolation and is it possible for the current implementation of crdb?
Cause RC isolation is the default isolation for some popular DBMS, such as Oracle and PG.

Hi @louis,

CockroachDB supports two isolation levels: snapshot isolation (SI) and serializable snapshot isolation (SSI).

In short, both SI and SSI are strictly stronger guarantees of isolation than read-committed. What this means is that read-committed permits certain “anomalies” that SI and SSI protect against. For example, the default RC isolation on Postgres permits non-repeatable reads (which means if transaction A reads some row(s) multiple times, the row(s) could have been modified by some other transaction B and produce different values).

You can find more information about isolation levels in the docs or if you’re feeling particularly adventurous the seminal ANSI critique paper may be of interest.

CockroachDB by default enables SSI which protects against all data anomalies and ensures true isolation. If you find that your workload(s) have high contention and are producing too many transaction retries, you may consider switching to SI (which does not protect against write skew anomalies).