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improve change

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This commit is contained in:
hchen9 2020-09-28 17:05:22 -07:00
parent 3ddcf590f6
commit fda6bde428
2 changed files with 3 additions and 1 deletions
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2
src/Interpreters/InterpreterSelectQuery.cpp
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@ -1112,12 +1112,14 @@ void InterpreterSelectQuery::executeFetchColumns(
/// Optimization for trivial query like SELECT count() FROM table.
bool optimize_trivial_count =
syntax_analyzer_result->optimize_trivial_count
&& settings.select_sequential_consistency
&& storage
&& !filter_info
&& processing_stage == QueryProcessingStage::FetchColumns
&& query_analyzer->hasAggregation()
&& (query_analyzer->aggregates().size() == 1)
&& typeid_cast<AggregateFunctionCount *>(query_analyzer->aggregates()[0].function.get());
if (optimize_trivial_count)
{

2
src/Interpreters/TreeRewriter.cpp
View File

@ -619,7 +619,7 @@ TreeRewriterResultPtr TreeRewriter::analyzeSelect(
result.ast_join = select_query->join();
if (result.optimize_trivial_count)
result.optimize_trivial_count = settings.optimize_trivial_count_query && settings.select_sequential_consistency &&
result.optimize_trivial_count = settings.optimize_trivial_count_query &&
!select_query->where() && !select_query->prewhere() && !select_query->groupBy() && !select_query->having() &&
!select_query->sampleSize() && !select_query->sampleOffset() && !select_query->final() &&
(tables_with_columns.size() < 2 || isLeft(result.analyzed_join->kind()));