[clickhouse] Skip emitting empty storage_health payloads

clickhouse/changelog.d/23553.fixed

@@ -0,0 +1 @@
+Skip emitting empty storage_health payloads when every parts-and-merges collection is empty.

clickhouse/datadog_checks/clickhouse/parts_and_merges.py

@@ -818,6 +818,8 @@ def _emit_events(
         thresholds: list[dict] | None = None,
     ) -> None:
         """Emit a per-cycle row-level payload consumed by dbm-events-processor."""
+        if not (parts or merges or mutations or replication_queue or detached_parts or thresholds):
+            return
         now_ms = int(time.time() * 1000)
         payload = {
             "host": self._check.reported_hostname,

clickhouse/tests/test_parts_and_merges.py

@@ -856,12 +856,27 @@ def test_emit_events_uses_query_activity_channel_not_metadata(check):
         mock.patch('datadog_checks.clickhouse.parts_and_merges.datadog_agent') as agent_mock,
     ):
         agent_mock.get_version.return_value = '7.64.0'
-        job._emit_events([], [], [], [], [])
+        job._emit_events(_collected_parts(), [], [], [], [])
 
     activity_mock.assert_called_once()
     metadata_mock.assert_not_called()
 
 
+def test_emit_events_skips_when_all_collections_empty(check):
+    job = check.parts_and_merges
+    job.tags = ['test:clickhouse']
+    job._tags_no_db = ['test:clickhouse']
+
+    with (
+        mock.patch.object(check, 'database_monitoring_query_activity') as activity_mock,
+        mock.patch('datadog_checks.clickhouse.parts_and_merges.datadog_agent') as agent_mock,
+    ):
+        agent_mock.get_version.return_value = '7.64.0'
+        job._emit_events([], [], [], [], [], [])
+
+    activity_mock.assert_not_called()
+
+
 # -----------------------------------------------------------------------------
 # Error handling
 # -----------------------------------------------------------------------------
@@ -907,6 +922,29 @@ def test_collect_and_emit_runs_with_partial_failures(check):
     assert payload['clickhouse']['active_merges'] == _collected_merges()
 
 
+def test_collect_and_emit_skips_when_all_collectors_empty(check):
+    job = check.parts_and_merges
+    job.tags = ['test:clickhouse']
+    job._tags_no_db = ['test:clickhouse']
+
+    with (
+        mock.patch.object(job, '_collect_parts', return_value=[]),
+        mock.patch.object(job, '_collect_merges', return_value=[]),
+        mock.patch.object(job, '_collect_mutations', return_value=[]),
+        mock.patch.object(job, '_collect_mutations_aggregated', return_value=[]),
+        mock.patch.object(job, '_collect_replication_queue', return_value=[]),
+        mock.patch.object(job, '_collect_replication_queue_aggregated', return_value=[]),
+        mock.patch.object(job, '_collect_detached_parts', return_value=[]),
+        mock.patch.object(job, '_collect_thresholds', return_value=[]),
+        mock.patch.object(check, 'database_monitoring_query_activity') as activity_mock,
+        mock.patch('datadog_checks.clickhouse.parts_and_merges.datadog_agent') as agent_mock,
+    ):
+        agent_mock.get_version.return_value = '7.64.0'
+        job._collect_and_emit()
+
+    activity_mock.assert_not_called()
+
+
 # -----------------------------------------------------------------------------
 # Cluster routing
 # -----------------------------------------------------------------------------