feat(trends): add moving average smoothing_intervals param

ee/clickhouse/queries/trends/total_volume.py

@@ -61,14 +61,31 @@ def _total_volume_query(self, entity: Entity, filter: Filter, team_id: int) -> T
                     **content_sql_params,
                     parsed_date_to=trend_event_query.parsed_date_to,
                     parsed_date_from=trend_event_query.parsed_date_from,
-                    **trend_event_query.active_user_params
+                    **trend_event_query.active_user_params,
                 )
             else:
                 content_sql = VOLUME_SQL.format(event_query=event_query, **content_sql_params)
 
             null_sql = NULL_SQL.format(trunc_func=trunc_func, interval_func=interval_func)
             params["interval"] = filter.interval
-            final_query = AGGREGATE_SQL.format(null_sql=null_sql, content_sql=content_sql)
+
+            # If we have a smoothing interval > 1 then add in the sql to
+            # handling rolling average. Else just do a sum. This is possibly an
+            # nessacary optimization.
+            if filter.smoothing_intervals > 1:
+                smoothing_operation = f"""
+                    AVG(SUM(total)) 
+                    OVER (
+                        ORDER BY day_start 
+                        ROWS BETWEEN {filter.smoothing_intervals - 1} PRECEDING 
+                        AND CURRENT ROW
+                    )"""
+            else:
+                smoothing_operation = "SUM(total)"
+
+            final_query = AGGREGATE_SQL.format(
+                null_sql=null_sql, content_sql=content_sql, smoothing_operation=smoothing_operation
+            )
             return final_query, params, self._parse_total_volume_result(filter)
 
     def _parse_total_volume_result(self, filter: Filter) -> Callable:

ee/clickhouse/sql/trends/aggregate.py

@@ -1,5 +1,13 @@
 AGGREGATE_SQL = """
 SELECT groupArray(day_start) as date, groupArray(count) as data FROM (
-    SELECT SUM(total) AS count, day_start from ({null_sql} UNION ALL {content_sql}) group by day_start order by day_start
+    SELECT {smoothing_operation} AS count, day_start 
+    from (
+        {null_sql} 
+        UNION ALL 
+        {content_sql}
+    ) 
+    group by day_start 
+    order by day_start
+    SETTINGS allow_experimental_window_functions = 1
 )
 """