Why run decisions in your database?
No network hop
Your data is already in PostgreSQL. Sending it to an external rules engine and back adds latency, failure modes, and operational complexity. pgdmn evaluates decisions right where the data lives.
Transactional consistency
Decision results are computed inside the same transaction as the data they depend on. No stale reads, no eventual consistency, no distributed coordination.
Auditable by default
The DMN model XML is a first-class PostgreSQL value. Store it in a table, version it with timestamps, and trace every evaluation back to the exact model version that produced the result.
Co-located with your data
Use lateral joins to evaluate a decision table against every row in a table in a single query. Batch thousands of decisions with no application code.
Standards-based
DMN is an OMG standard supported by tools from Camunda, Trisotech, and others. Author models visually, test them independently, and deploy to PostgreSQL.