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Author: Tomasz Zórawik

sqlmesh/core/plan/builder.py

@@ -683,8 +683,8 @@ def _categorize_snapshot(
             if snapshot.is_materialized_view and not forward_only:
                 # We categorize changes as breaking to allow for instantaneous switches in a virtual layer.
                 # Otherwise, there might be a potentially long downtime during MVs recreation.
-                # In the case of forward-only changes this optimization is not applicable because we continue using the
-                # same (existing) table version.
+                # In the case of forward-only changes this optimization is not applicable because we want to continue
+                # using the same (existing) table version.
                 snapshot.categorize_as(SnapshotChangeCategory.INDIRECT_BREAKING, forward_only)
                 return
 

tests/core/test_plan.py

@@ -4239,4 +4239,6 @@ def test_forward_only_indirect_change_to_materialized_view(make_snapshot):
 
     PlanBuilder(context_diff, forward_only=True).build()
 
+    # Forward-only indirect changes to MVs should not always be classified as indirect breaking.
+    # Instead, we want to preserve the standard categorization.
     assert snapshot_b_new.change_category == SnapshotChangeCategory.INDIRECT_NON_BREAKING