Reach 100% statement coverage across the entire module without exclusions. Test SQL failures with preserved PostgreSQL causes, invalid rows, missing receive offsets, transaction begin failure, empty operations, factory initialization and actual event dispatch. Close factory query rows to avoid connection-pool exhaustion and remove an unreachable successful-BeginTx nil check. Enforce full raw coverage and race detection on branch/tag pipelines. Validated Go 1.23.4 with PostgreSQL 12: all tests -race pass, go vet and go mod verify pass, coverage 100.0%.