How to use this reference
For an owned application, document the invariant, the transaction boundary and the isolation or locking assumptions that protect it. As an editorial application, connect approval-state decisions to their database consistency requirements; do not assume that repeating only the final write revalidates an earlier decision.
Before reading
- Basic database transactions and isolation levels
- Application business rules and state transitions
Context and limits
- PostgreSQL-specific semantics must not be assumed for another database or version. The documented serializable-integrity approach requires consistent participation by relevant reads and writes.
- The documented serializable protection does not extend to hot standby or logical replicas; deployment boundaries matter.
- Unique-key and exclusion-constraint errors can be persistent rather than transient; they do not justify blanket retries. Retrying does not guarantee eventual completion.
- This is conceptual defensive education, not a vulnerability finding, testing authorization or executable concurrency recipe.
Sources and provenance
- PostgreSQL 18: Data Consistency Checks at the Application Level PostgreSQL Global Development Group · reviewed 2026-10-03
- PostgreSQL 18: Serialization Failure Handling PostgreSQL Global Development Group · reviewed 2026-10-03
Record reviewed 2026-10-03. Snapshot 53796974ace8. Open the complete JSON contract.