fix: keep migration and blocker SQL postgres-safe

central/tests/test_operational_view_models.py

@@ -1,10 +1,11 @@
 from datetime import datetime, timedelta, timezone
 
 from sqlalchemy import event
+from sqlalchemy.dialects import postgresql
 
 from central.app.audit import record_audit
 from central.app.blocked_products import upsert_blocker
-from central.app.control_plane import dashboard_summary, list_blockers, list_installations, list_jobs
+from central.app.control_plane import _blocker_breakdown_query, dashboard_summary, list_blockers, list_installations, list_jobs
 from central.app.events import record_event
 from central.app.models import Agent, AgentSnapshot, AuditEvent, BlockedProduct, Installation, Job, Tenant
 from central.tests.test_control_plane import setup_db
@@ -310,3 +311,13 @@ def test_lowercase_required_blocker_field_reaches_attention_candidates():
         attention = dashboard_summary(session, now=NOW)["attention_items"]
 
         assert any(item["link"] == f"/blockers/{blocker.id}" for item in attention)
+
+
+def test_blocker_breakdown_query_groups_on_same_postgres_expression():
+    from sqlalchemy import select
+
+    query = select(BlockedProduct, Tenant).join(Tenant, Tenant.id == BlockedProduct.tenant_id)
+    sql = str(_blocker_breakdown_query(query).compile(dialect=postgresql.dialect()))
+
+    assert "GROUP BY blocked_products.field" in sql
+    assert "GROUP BY coalesce" not in sql