Preparation [#CLICKHOUSE-31].

dbms/src/Interpreters/InterpreterSelectQuery.cpp

@@ -70,6 +70,7 @@ void InterpreterSelectQuery::init(BlockInputStreamPtr input, const Names & requi
     ProfileEvents::increment(ProfileEvents::SelectQuery);
 
     initSettings();
+    const Settings & settings = context.getSettingsRef();
 
     original_max_threads = settings.max_threads;
 
@@ -369,6 +370,8 @@ BlockIO InterpreterSelectQuery::execute()
         /// Constraints apply only to the final result.
         if (to_stage == QueryProcessingStage::Complete)
         {
+            const Settings & settings = context.getSettingsRef();
+
             IProfilingBlockInputStream::LocalLimits limits;
             limits.mode = IProfilingBlockInputStream::LIMITS_CURRENT;
             limits.max_rows_to_read = settings.limits.max_result_rows;
@@ -431,6 +434,8 @@ void InterpreterSelectQuery::executeSingleQuery()
 
     LOG_TRACE(log, QueryProcessingStage::toString(from_stage) << " -> " << QueryProcessingStage::toString(to_stage));
 
+    const Settings & settings = context.getSettingsRef();
+
     if (to_stage > QueryProcessingStage::FetchColumns)
     {
         bool has_join        = false;
@@ -777,6 +782,7 @@ QueryProcessingStage::Enum InterpreterSelectQuery::executeFetchColumns()
      *  and there must be an original value of max_threads, not an increased value.
      */
     bool is_remote = false;
+    Settings & settings = context.getSettingsRef();
     Settings settings_for_storage = settings;
     if (storage && storage->isRemote())
     {
@@ -913,6 +919,8 @@ void InterpreterSelectQuery::executeAggregation(ExpressionActionsPtr expression,
     AggregateDescriptions aggregates;
     query_analyzer->getAggregateInfo(key_names, aggregates);
 
+    const Settings & settings = context.getSettingsRef();
+
     /** Two-level aggregation is useful in two cases:
       * 1. Parallel aggregation is done, and the results should be measured in parallel.
       * 2. An aggregation is done with store of temporary data on the disk, and they need to be merged memory efficient.
@@ -980,6 +988,8 @@ void InterpreterSelectQuery::executeMergeAggregated(bool overflow_row, bool fina
 
     Aggregator::Params params(key_names, aggregates, overflow_row);
 
+    const Settings & settings = context.getSettingsRef();
+
     if (!settings.distributed_aggregation_memory_efficient)
     {
         /// We union several sources into one, parallelizing the work.
@@ -1014,6 +1024,8 @@ void InterpreterSelectQuery::executeTotalsAndHaving(bool has_having, ExpressionA
 {
     executeUnion();
 
+    const Settings & settings = context.getSettingsRef();
+
     streams[0] = std::make_shared<TotalsHavingBlockInputStream>(
         streams[0], overflow_row, expression,
         has_having ? query.having_expression->getColumnName() : "", settings.totals_mode, settings.totals_auto_threshold);
@@ -1069,6 +1081,8 @@ void InterpreterSelectQuery::executeOrder()
     SortDescription order_descr = getSortDescription(query);
     size_t limit = getLimitForSorting(query);
 
+    const Settings & settings = context.getSettingsRef();
+
     transformStreams([&](auto & stream)
     {
         auto sorting_stream = std::make_shared<PartialSortingBlockInputStream>(stream, order_descr, limit);
@@ -1099,6 +1113,8 @@ void InterpreterSelectQuery::executeMergeSorted()
     SortDescription order_descr = getSortDescription(query);
     size_t limit = getLimitForSorting(query);
 
+    const Settings & settings = context.getSettingsRef();
+
     /// If there are several streams, then we merge them into one
     if (hasMoreThanOneStream())
     {
@@ -1130,6 +1146,8 @@ void InterpreterSelectQuery::executeDistinct(bool before_order, Names columns)
 {
     if (query.distinct)
     {
+        const Settings & settings = context.getSettingsRef();
+
         size_t limit_length = 0;
         size_t limit_offset = 0;
         getLimitLengthAndOffset(query, limit_length, limit_offset);
@@ -1159,6 +1177,8 @@ void InterpreterSelectQuery::executeUnion()
     /// If there are still several streams, then we combine them into one
     if (hasMoreThanOneStream())
     {
+        const Settings & settings = context.getSettingsRef();
+
         streams[0] = std::make_shared<UnionBlockInputStream<>>(streams, stream_with_non_joined_data, settings.max_threads);
         stream_with_non_joined_data = nullptr;
         streams.resize(1);
@@ -1281,6 +1301,8 @@ void InterpreterSelectQuery::executeSubqueriesInSetsAndJoins(SubqueriesForSets &
         for (auto & elem : subqueries_for_sets)
             elem.second.table.reset();
 
+    const Settings & settings = context.getSettingsRef();
+
     executeUnion();
     streams[0] = std::make_shared<CreatingSetsBlockInputStream>(streams[0], subqueries_for_sets, settings.limits);
 }
@@ -1318,8 +1340,6 @@ void InterpreterSelectQuery::initSettings()
 {
     if (query.settings)
         InterpreterSetQuery(query.settings, context).executeForCurrentContext();
-
-    settings = context.getSettings();
 }
 
 }

dbms/src/Interpreters/InterpreterSelectQuery.h

@@ -157,7 +157,6 @@ private:
     void ignoreWithTotals();
 
     /** Если в запросе SELECT есть секция SETTINGS, то применить настройки из неё.
-      * Затем достать настройки из context и поместить их в settings.
       *
       * Секция SETTINGS - настройки для конкретного запроса.
       * Обычно настройки могут быть переданы другими способами, не внутри запроса.
@@ -168,7 +167,6 @@ private:
     ASTPtr query_ptr;
     ASTSelectQuery & query;
     Context context;
-    Settings settings;
     size_t original_max_threads; /// В settings настройка max_threads может быть изменена. В original_max_threads сохраняется изначальное значение.
     QueryProcessingStage::Enum to_stage;
     size_t subquery_depth;