Fix: Evaluation of metadata snapshots with audit changes

sqlmesh/core/plan/stages.py

@@ -574,23 +574,31 @@ def _get_audit_only_snapshots(
     ) -> t.Dict[SnapshotId, Snapshot]:
         metadata_snapshots = []
         for snapshot in new_snapshots.values():
-            if not snapshot.is_metadata or not snapshot.is_model or not snapshot.evaluatable:
+            if (
+                not snapshot.is_metadata
+                or not snapshot.is_model
+                or not snapshot.evaluatable
+                or not snapshot.previous_version
+            ):
                 continue
 
             metadata_snapshots.append(snapshot)
 
         # Bulk load all the previous snapshots
-        previous_snapshots = self.state_reader.get_snapshots(
-            [
-                s.previous_version.snapshot_id(s.name)
-                for s in metadata_snapshots
-                if s.previous_version
-            ]
-        ).values()
+        previous_snapshot_ids = [
+            s.previous_version.snapshot_id(s.name) for s in metadata_snapshots if s.previous_version
+        ]
+        previous_snapshots = {
+            s.name: s for s in self.state_reader.get_snapshots(previous_snapshot_ids).values()
+        }
 
         # Check if any of the snapshots have modifications to the audits field by comparing the hashes
         audit_snapshots = {}
-        for snapshot, previous_snapshot in zip(metadata_snapshots, previous_snapshots):
+        for snapshot in metadata_snapshots:
+            if snapshot.name not in previous_snapshots:
+                continue
+
+            previous_snapshot = previous_snapshots[snapshot.name]
             new_audits_hash = snapshot.model.audit_metadata_hash()
             previous_audit_hash = previous_snapshot.model.audit_metadata_hash()
 

sqlmesh/core/scheduler.py

@@ -626,6 +626,9 @@ def _dag(
         dag = DAG[SchedulingUnit]()
 
         for snapshot_id in snapshot_dag:
+            if snapshot_id.name not in self.snapshots_by_name:
+                continue
+
             snapshot = self.snapshots_by_name[snapshot_id.name]
             intervals = intervals_per_snapshot.get(snapshot.name, [])
 

tests/core/test_integration.py

@@ -6294,6 +6294,31 @@ def test_restatement_shouldnt_backfill_beyond_prod_intervals(init_and_plan_conte
         ].intervals[-1][1] == to_timestamp("2023-01-08 00:00:00 UTC")
 
 
+@time_machine.travel("2023-01-08 15:00:00 UTC")
+@use_terminal_console
+def test_audit_only_metadata_change(init_and_plan_context: t.Callable):
+    context, plan = init_and_plan_context("examples/sushi")
+    context.apply(plan)
+
+    # Add a new audit
+    model = context.get_model("sushi.waiter_revenue_by_day")
+    audits = model.audits.copy()
+    audits.append(("number_of_rows", {"threshold": exp.Literal.number(1)}))
+    model = model.copy(update={"audits": audits})
+    context.upsert_model(model)
+
+    plan = context.plan_builder("prod", skip_tests=True).build()
+    assert len(plan.new_snapshots) == 2
+    assert all(s.change_category.is_metadata for s in plan.new_snapshots)
+    assert not plan.missing_intervals
+
+    with capture_output() as output:
+        context.apply(plan)
+
+    assert "Auditing models" in output.stdout
+    assert model.name in output.stdout
+
+
 def initial_add(context: Context, environment: str):
     assert not context.state_reader.get_environment(environment)