fix comments

pingcap · Nov 28, 2022 · 6d2ee5a · 6d2ee5a
1 parent 58045f0
commit 6d2ee5a
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Showing 2 changed files with 4 additions and 7 deletions.
diff --git a/dbms/src/Common/TiFlashException.h b/dbms/src/Common/TiFlashException.h
@@ -155,7 +155,6 @@ namespace DB
             "");)                                                                                                                    \
     C(Types, E(Truncated, "Data is truncated during conversion.", "", ""); E(WrongValue, "Input value is in wrong format", "", "");) \
     C(Expression, E(DivisionByZero, "Division by 0.", "", "");)                                                                      \
-    C(Storage, E(CastError, "Storage cast error.", "", "");)                                                                         \
     C(Checksum,                                                                                                                      \
         E(Missing, "Checksum info for disk I/O checksum was expected but not found.",                                                \
             "This may be caused by a failure during data file format upgrade or file lost; \n"                                       \

diff --git a/dbms/src/Flash/Coprocessor/DAGStorageInterpreter.cpp b/dbms/src/Flash/Coprocessor/DAGStorageInterpreter.cpp
@@ -783,13 +783,11 @@ void DAGStorageInterpreter::buildLocalStreamsForPhysicalTable(
             QueryProcessingStage::Enum from_stage = QueryProcessingStage::FetchColumns;
             const auto & scan_context = dag_context.scan_context_map.at(table_scan.getTableScanExecutorID());
 
-            // We need read with scan_context here, while IStorage::read() can't support it.
-            // Thus, we need first to cast to StorageDeltaMerge to call the corresponding read() function.
+            // We want to collect performance metrics in storage level, thus we need read with scan_context here.
+            // while IStorage::read() can't support it, and only StorageDeltaMerge support to read with scan_context to collect the information.
+            // Thus, storage must cast to StorageDeltaMergePtr here to call the corresponding read() function.
             StorageDeltaMergePtr delta_merge_storage = std::dynamic_pointer_cast<StorageDeltaMerge>(storage);
-            if (delta_merge_storage == nullptr)
-            {
-                throw TiFlashException(fmt::format("delta_merge_storage which cast from storage is null"), Errors::Storage::CastError);
-            }
+            RUNTIME_CHECK_MSG(delta_merge_storage != nullptr, "delta_merge_storage which cast from storage is null");
             pipeline.streams = delta_merge_storage->read(required_columns, query_info, context, from_stage, max_block_size, max_streams, scan_context);
 
             injectFailPointForLocalRead(query_info);