AWS Introduces Foreign Key Constraints in Aurora DSQL

Aurora DSQL now enforces foreign-key relationships inside its distributed PostgreSQL-compatible database—a feature whose absence had been an adoption blocker for some users. The interesting part is how it handles concurrency: it checks relationships against each transaction’s snapshot, then uses commit-time conflict detection rather than locking tables. A conflicting transaction fails with a serialization error, so applications need retry logic; the extra integrity checks also add reads, which AWS says users should benchmark.

The InfoQ report quotes an AWS engineer describing the non-blocking design and a practitioner welcoming the feature for brownfield migrations. InfoQ has no article comment section. AWS documents the mechanics and caveats in its foreign-key guide and announced the feature August 27.