No transactions across shards is a bummer as well. Feels like planetscale might not be the best choice for small to medium projects, despite their improvements in developer experience.
Re:Comparing AWS's RDS and PlanetScale
by derekperkins on Wednesday October 13, 2021 @11:30AM
(#28853433)
In practice this doesn't turn out to be a major issue, since a good design will keep >99% of queries/transactions on a single shard.
4 years of Vitess in prod, also a maintainer
https://vitess.io/docs/reference/compatibility/mysql-compati...