Conflict-serializability is decided by a deterministic graph cycle check.
highlighted = computed this step
Why the check is exact
The engine does not estimate serializability. It builds a graph from conflicts, checks for a cycle, and renders the resulting facts. Note: deterministic graph order makes the result stable.
exact graph check
Deterministic facts
The recomputed edge count is 2 and the cycle length is 2. Note: rerunning the compile produces the same graph facts.
edges=2,cycle length=2
conflict-serializability is an exact SUFFICIENT criterion; a cyclic precedence graph is provably not conflict-serializable; view-serializability, lock scheduling, and recovery are beyond these tiny traces - no product claims.
Summary
The exact core is conflict edges plus a cycle check. Note: conflict-serializability is exact here; view-serializability, locks, and recovery are deferred.