Disable backfill sorting by default (#476)

Author: yl-lisen

src/Core/Settings.h

@@ -790,7 +790,8 @@ static constexpr UInt64 operator""_GiB(unsigned long long value)
     M(UInt64, keep_windows, 0, "How many streaming windows to keep from recycling", 0) \
     M(String, seek_to, "", "Seeking to an offset of the streaming/historical store to seek", 0) \
     M(Bool, enable_backfill_from_historical_store, true, "Enable backfill data from historical data store", 0) \
-    M(Bool, emit_aggregated_during_backfill, true, "Enable emit intermediate aggr result during backfill historical data", 0) \
+    M(Bool, emit_aggregated_during_backfill, false, "Enable emit intermediate aggr result during backfill historical data", 0) \
+    M(Bool, force_backfill_in_order, false, "Requires backfill data in order", 0) \
     M(Bool, include_internal_streams, false, "Show internal streams on SHOW streams query.", 0) \
     M(UInt64, join_max_buffered_bytes, 524288000, "Max buffered bytes for stream to stream join", 0) \
     M(UInt64, join_buffered_data_block_size, 0, "For streaming join, when buffered data in memory, the data block size directs to merge small data blocks to form bigger ones to improve memory efficiency. 0 means disable merging small data blocks.", 0) \

src/Interpreters/InterpreterSelectQuery.cpp

@@ -3434,9 +3434,11 @@ void InterpreterSelectQuery::finalCheckAndOptimizeForStreamingQuery()
                 context->setSetting("enable_backfill_from_historical_store", false);
         }
 
-        /// Optimization: no requires backfill data in order for global aggregation with settings `emit_aggregated_during_backfill = false`.
-        if (!settings.emit_aggregated_during_backfill.value && hasStreamingGlobalAggregation())
-            query_info.require_in_order_backfill = false;
+        /// Usually, we don't care whether the backfilled data is in order. Excepts:
+        /// 1) User require backfill data in order
+        /// 2) User need window aggr emit result during backfill (it expects that process data in ascending event time)
+        if (settings.force_backfill_in_order.value || (settings.emit_aggregated_during_backfill.value && hasAggregation() && hasStreamingWindowFunc()))
+            query_info.require_in_order_backfill = true;
     }
     else
     {

src/Storages/SelectQueryInfo.h

@@ -184,7 +184,7 @@ struct SelectQueryInfo
     SeekToInfoPtr seek_to_info_of_right_stream; /// Rewind info for right streaming store in streaming query
 
     /// if is true, means need sort backfill input by event time (ascending)
-    bool require_in_order_backfill = true;
+    bool require_in_order_backfill = false;
 
     Streaming::WindowParamsPtr streaming_window_params;