Newer PostgreSQL versions are better. Yet still not quite as robust or easy as MySQL.
At a certain scale even MySQL upgrades can be painful. At least when you cannot spare more than a few minutes of downtime.
https://jepsen.io/analyses/mysql-8.0.34 ( MySQL 8.0.34 2023-12-19 )
HN: https://news.ycombinator.com/item?id=38695750
"MySQL is a popular relational database. We revisit Kleppmann’s 2014 Hermitage and confirm that MySQL’s Repeatable Read still allows G2-item, G-single, and lost update. Using our transaction consistency checker Elle, we show that MySQL Repeatable Read also violates internal consistency. Furthermore, it violates Monotonic Atomic View: transactions can observe some of another transaction’s effects, then later fail to observe other effects of that same transaction. We demonstrate violations of ANSI SQL’s requirements for Repeatable Read. We believe MySQL Repeatable Read is somewhat stronger than Read Committed. As a lagniappe, we show that AWS RDS MySQL clusters routinely violate Serializability."
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https://jepsen.io/analyses/postgresql-12.3 ( PostgreSQL 12.3 2020-06-12 )
HN: https://news.ycombinator.com/item?id=23498781
"PostgreSQL is a widely-known relational database system. We evaluated PostgreSQL using Jepsen’s new transactional isolation checker Elle, and found that transactions executed with serializable isolation on a single PostgreSQL instance were not, in fact, serializable. Under normal operation, transactions could occasionally exhibit G2-item: an anomaly involving a set of transactions which (roughly speaking) mutually fail to observe each other’s writes. In addition, we found frequent instances of G2-item under PostgreSQL “repeatable read”, which is explicitly proscribed by commonly-cited formalizations of repeatable read. As previously reported by Martin Kleppmann, this is due to the fact that PostgreSQL “repeatable read” is actually snapshot isolation. This behavior is allowable due to long-discussed ambiguities in the ANSI SQL standard, but could be surprising for users familiar with the literature. A patch for the bug we found in serializability is scheduled for the next minor release, on August 13th, and the presence of G2-item under repeatable read could be readily addressed through documentation."