Yes. I know there are other ways to do simple counters. The counter-example broadly applies to multi-statement operations that feed the output of reads into writes, i.e. in general transactions.
And yes, the defaults on many systems are low, but you can turn them up if you have a transactional workload. Read-committed might be fine for a Drupal backend, but it's not truly transactional.
One of the relevant points Peter makes is that weaker isolation may work ok at low contention and low scale, which matches most DB workloads, but probably not the ones people on HN care about.
And yes, the defaults on many systems are low, but you can turn them up if you have a transactional workload. Read-committed might be fine for a Drupal backend, but it's not truly transactional.
Related and neat post:
http://www.bailis.org/blog/understanding-weak-isolation-is-a...
One of the relevant points Peter makes is that weaker isolation may work ok at low contention and low scale, which matches most DB workloads, but probably not the ones people on HN care about.