ClickHouse

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#include <Processors/QueryPlan/DistributedCreateLocalPlan.h>
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#include <Common/config_version.h>
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#include <Common/checkStackSize.h>
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#include <Core/ProtocolDefines.h>
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#include <Interpreters/ActionsDAG.h>
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#include <Interpreters/InterpreterSelectQuery.h>
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#include <Interpreters/InterpreterSelectQueryAnalyzer.h>
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#include <Processors/QueryPlan/ExpressionStep.h>
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namespace DB
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{
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namespace
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{
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void addConvertingActions(QueryPlan & plan, const Block & header, bool has_missing_objects)
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{
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    if (blocksHaveEqualStructure(plan.getCurrentDataStream().header, header))
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        return;
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    auto mode = has_missing_objects ? ActionsDAG::MatchColumnsMode::Position : ActionsDAG::MatchColumnsMode::Name;
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    auto get_converting_dag = [mode](const Block & block_, const Block & header_)
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    {
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        /// Convert header structure to expected.
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        /// Also we ignore constants from result and replace it with constants from header.
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        /// It is needed for functions like `now64()` or `randConstant()` because their values may be different.
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        return ActionsDAG::makeConvertingActions(
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            block_.getColumnsWithTypeAndName(),
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            header_.getColumnsWithTypeAndName(),
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            mode,
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            true);
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    };
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    auto convert_actions_dag = get_converting_dag(plan.getCurrentDataStream().header, header);
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    auto converting = std::make_unique<ExpressionStep>(plan.getCurrentDataStream(), convert_actions_dag);
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    plan.addStep(std::move(converting));
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}
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}
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std::unique_ptr<QueryPlan> createLocalPlan(
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    const ASTPtr & query_ast,
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    const Block & header,
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    ContextPtr context,
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    QueryProcessingStage::Enum processed_stage,
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    size_t shard_num,
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    size_t shard_count,
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    bool has_missing_objects)
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{
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    checkStackSize();
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    auto query_plan = std::make_unique<QueryPlan>();
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    auto new_context = Context::createCopy(context);
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    /// Do not push down limit to local plan, as it will break `rows_before_limit_at_least` counter.
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    if (processed_stage == QueryProcessingStage::WithMergeableStateAfterAggregationAndLimit)
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        processed_stage = QueryProcessingStage::WithMergeableStateAfterAggregation;
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    /// Do not apply AST optimizations, because query
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    /// is already optimized and some optimizations
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    /// can be applied only for non-distributed tables
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    /// and we can produce query, inconsistent with remote plans.
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    auto select_query_options = SelectQueryOptions(processed_stage)
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        .setShardInfo(static_cast<UInt32>(shard_num), static_cast<UInt32>(shard_count))
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        .ignoreASTOptimizations();
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    if (context->getSettingsRef().allow_experimental_analyzer)
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    {
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        /// For Analyzer, identifier in GROUP BY/ORDER BY/LIMIT BY lists has been resolved to
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        /// ConstantNode in QueryTree if it is an alias of a constant, so we should not replace
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        /// ConstantNode with ProjectionNode again(https://github.com/ClickHouse/ClickHouse/issues/62289).
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        new_context->setSetting("enable_positional_arguments", Field(false));
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        auto interpreter = InterpreterSelectQueryAnalyzer(query_ast, new_context, select_query_options);
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        query_plan = std::make_unique<QueryPlan>(std::move(interpreter).extractQueryPlan());
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    }
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    else
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    {
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        auto interpreter = InterpreterSelectQuery(query_ast, new_context, select_query_options);
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        interpreter.buildQueryPlan(*query_plan);
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    }
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    addConvertingActions(*query_plan, header, has_missing_objects);
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    return query_plan;
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}
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}
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