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https://github.com/ClickHouse/ClickHouse.git
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636 lines
20 KiB
C++
636 lines
20 KiB
C++
#include <optional>
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#include <Core/Field.h>
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#include <Columns/ColumnsNumber.h>
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#include <Columns/ColumnTuple.h>
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#include <Common/typeid_cast.h>
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#include <DataTypes/DataTypeTuple.h>
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#include <DataTypes/DataTypeNullable.h>
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#include <Parsers/ASTExpressionList.h>
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#include <Parsers/ASTFunction.h>
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#include <Parsers/ASTLiteral.h>
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#include <Interpreters/Set.h>
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#include <Interpreters/convertFieldToType.h>
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#include <Interpreters/evaluateConstantExpression.h>
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#include <Interpreters/NullableUtils.h>
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#include <Interpreters/sortBlock.h>
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#include <Interpreters/castColumn.h>
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#include <Interpreters/Context.h>
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#include <Processors/Chunk.h>
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#include <Storages/MergeTree/KeyCondition.h>
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#include <base/range.h>
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#include <base/sort.h>
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#include <DataTypes/DataTypeLowCardinality.h>
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namespace DB
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{
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namespace ErrorCodes
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{
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extern const int LOGICAL_ERROR;
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extern const int SET_SIZE_LIMIT_EXCEEDED;
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extern const int TYPE_MISMATCH;
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extern const int NUMBER_OF_COLUMNS_DOESNT_MATCH;
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}
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template <typename Method>
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void NO_INLINE Set::insertFromBlockImpl(
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Method & method,
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const ColumnRawPtrs & key_columns,
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size_t rows,
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SetVariants & variants,
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ConstNullMapPtr null_map,
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ColumnUInt8::Container * out_filter)
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{
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if (null_map)
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{
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if (out_filter)
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insertFromBlockImplCase<Method, true, true>(method, key_columns, rows, variants, null_map, out_filter);
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else
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insertFromBlockImplCase<Method, true, false>(method, key_columns, rows, variants, null_map, out_filter);
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}
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else
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{
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if (out_filter)
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insertFromBlockImplCase<Method, false, true>(method, key_columns, rows, variants, null_map, out_filter);
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else
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insertFromBlockImplCase<Method, false, false>(method, key_columns, rows, variants, null_map, out_filter);
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}
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}
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template <typename Method, bool has_null_map, bool build_filter>
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void NO_INLINE Set::insertFromBlockImplCase(
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Method & method,
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const ColumnRawPtrs & key_columns,
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size_t rows,
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SetVariants & variants,
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[[maybe_unused]] ConstNullMapPtr null_map,
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[[maybe_unused]] ColumnUInt8::Container * out_filter)
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{
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typename Method::State state(key_columns, key_sizes, nullptr);
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/// For all rows
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for (size_t i = 0; i < rows; ++i)
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{
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if constexpr (has_null_map)
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{
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if ((*null_map)[i])
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{
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if constexpr (build_filter)
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{
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(*out_filter)[i] = false;
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}
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continue;
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}
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}
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[[maybe_unused]] auto emplace_result = state.emplaceKey(method.data, i, variants.string_pool);
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if constexpr (build_filter)
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(*out_filter)[i] = emplace_result.isInserted();
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}
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}
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void Set::setHeader(const ColumnsWithTypeAndName & header)
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{
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std::lock_guard lock(rwlock);
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if (!data.empty())
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return;
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keys_size = header.size();
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ColumnRawPtrs key_columns;
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key_columns.reserve(keys_size);
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data_types.reserve(keys_size);
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set_elements_types.reserve(keys_size);
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/// The constant columns to the right of IN are not supported directly. For this, they first materialize.
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Columns materialized_columns;
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/// Remember the columns we will work with
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for (size_t i = 0; i < keys_size; ++i)
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{
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materialized_columns.emplace_back(header.at(i).column->convertToFullColumnIfConst());
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key_columns.emplace_back(materialized_columns.back().get());
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data_types.emplace_back(header.at(i).type);
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set_elements_types.emplace_back(header.at(i).type);
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/// Convert low cardinality column to full.
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if (const auto * low_cardinality_type = typeid_cast<const DataTypeLowCardinality *>(data_types.back().get()))
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{
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data_types.back() = low_cardinality_type->getDictionaryType();
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set_elements_types.back() = low_cardinality_type->getDictionaryType();
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materialized_columns.emplace_back(key_columns.back()->convertToFullColumnIfLowCardinality());
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key_columns.back() = materialized_columns.back().get();
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}
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}
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/// We will insert to the Set only keys, where all components are not NULL.
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ConstNullMapPtr null_map{};
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ColumnPtr null_map_holder;
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if (!transform_null_in)
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{
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/// We convert nullable columns to non nullable we also need to update nullable types
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for (size_t i = 0; i < set_elements_types.size(); ++i)
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{
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data_types[i] = removeNullable(data_types[i]);
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set_elements_types[i] = removeNullable(set_elements_types[i]);
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}
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extractNestedColumnsAndNullMap(key_columns, null_map);
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}
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if (fill_set_elements)
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{
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/// Create empty columns with set values in advance.
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/// It is needed because set may be empty, so method 'insertFromBlock' will be never called.
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set_elements.reserve(keys_size);
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for (const auto & type : set_elements_types)
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set_elements.emplace_back(type->createColumn());
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}
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/// Choose data structure to use for the set.
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data.init(data.chooseMethod(key_columns, key_sizes));
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}
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bool Set::insertFromBlock(const ColumnsWithTypeAndName & columns)
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{
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Columns cols;
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cols.reserve(columns.size());
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for (const auto & column : columns)
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cols.emplace_back(column.column);
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return insertFromBlock(cols);
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}
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bool Set::insertFromBlock(const Columns & columns)
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{
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std::lock_guard<std::shared_mutex> lock(rwlock);
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if (data.empty())
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throw Exception("Method Set::setHeader must be called before Set::insertFromBlock", ErrorCodes::LOGICAL_ERROR);
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ColumnRawPtrs key_columns;
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key_columns.reserve(keys_size);
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/// The constant columns to the right of IN are not supported directly. For this, they first materialize.
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Columns materialized_columns;
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/// Remember the columns we will work with
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for (size_t i = 0; i < keys_size; ++i)
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{
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materialized_columns.emplace_back(columns.at(i)->convertToFullIfNeeded());
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key_columns.emplace_back(materialized_columns.back().get());
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}
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size_t rows = columns.at(0)->size();
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/// We will insert to the Set only keys, where all components are not NULL.
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ConstNullMapPtr null_map{};
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ColumnPtr null_map_holder;
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if (!transform_null_in)
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null_map_holder = extractNestedColumnsAndNullMap(key_columns, null_map);
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/// Filter to extract distinct values from the block.
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ColumnUInt8::MutablePtr filter;
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if (fill_set_elements)
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filter = ColumnUInt8::create(rows);
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switch (data.type)
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{
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case SetVariants::Type::EMPTY:
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break;
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#define M(NAME) \
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case SetVariants::Type::NAME: \
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insertFromBlockImpl(*data.NAME, key_columns, rows, data, null_map, filter ? &filter->getData() : nullptr); \
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break;
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APPLY_FOR_SET_VARIANTS(M)
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#undef M
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}
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if (fill_set_elements)
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{
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for (size_t i = 0; i < keys_size; ++i)
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{
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auto filtered_column = key_columns[i]->filter(filter->getData(), rows);
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if (set_elements[i]->empty())
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set_elements[i] = filtered_column;
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else
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set_elements[i]->insertRangeFrom(*filtered_column, 0, filtered_column->size());
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if (transform_null_in && null_map_holder)
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set_elements[i]->insert(Null{});
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}
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}
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return limits.check(data.getTotalRowCount(), data.getTotalByteCount(), "IN-set", ErrorCodes::SET_SIZE_LIMIT_EXCEEDED);
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}
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ColumnPtr Set::execute(const ColumnsWithTypeAndName & columns, bool negative) const
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{
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size_t num_key_columns = columns.size();
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if (0 == num_key_columns)
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throw Exception("Logical error: no columns passed to Set::execute method.", ErrorCodes::LOGICAL_ERROR);
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auto res = ColumnUInt8::create();
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ColumnUInt8::Container & vec_res = res->getData();
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vec_res.resize(columns.at(0).column->size());
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if (vec_res.empty())
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return res;
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std::shared_lock lock(rwlock);
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/// If the set is empty.
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if (data_types.empty())
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{
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if (negative)
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memset(vec_res.data(), 1, vec_res.size());
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else
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memset(vec_res.data(), 0, vec_res.size());
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return res;
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}
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checkColumnsNumber(num_key_columns);
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/// Remember the columns we will work with. Also check that the data types are correct.
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ColumnRawPtrs key_columns;
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key_columns.reserve(num_key_columns);
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/// The constant columns to the left of IN are not supported directly. For this, they first materialize.
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Columns materialized_columns;
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materialized_columns.reserve(num_key_columns);
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for (size_t i = 0; i < num_key_columns; ++i)
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{
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ColumnPtr result;
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const auto & column_before_cast = columns.at(i);
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ColumnWithTypeAndName column_to_cast
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= {column_before_cast.column->convertToFullColumnIfConst(), column_before_cast.type, column_before_cast.name};
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if (!transform_null_in && data_types[i]->canBeInsideNullable())
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{
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result = castColumnAccurateOrNull(column_to_cast, data_types[i]);
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}
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else
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{
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result = castColumnAccurate(column_to_cast, data_types[i]);
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}
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materialized_columns.emplace_back() = result;
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key_columns.emplace_back() = materialized_columns.back().get();
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}
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/// We will check existence in Set only for keys whose components do not contain any NULL value.
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ConstNullMapPtr null_map{};
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ColumnPtr null_map_holder;
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if (!transform_null_in)
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null_map_holder = extractNestedColumnsAndNullMap(key_columns, null_map);
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executeOrdinary(key_columns, vec_res, negative, null_map);
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return res;
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}
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bool Set::empty() const
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{
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std::shared_lock lock(rwlock);
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return data.empty();
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}
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size_t Set::getTotalRowCount() const
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{
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std::shared_lock lock(rwlock);
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return data.getTotalRowCount();
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}
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size_t Set::getTotalByteCount() const
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{
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std::shared_lock lock(rwlock);
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return data.getTotalByteCount();
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}
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template <typename Method>
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void NO_INLINE Set::executeImpl(
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Method & method,
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const ColumnRawPtrs & key_columns,
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ColumnUInt8::Container & vec_res,
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bool negative,
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size_t rows,
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ConstNullMapPtr null_map) const
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{
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if (null_map)
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executeImplCase<Method, true>(method, key_columns, vec_res, negative, rows, null_map);
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else
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executeImplCase<Method, false>(method, key_columns, vec_res, negative, rows, null_map);
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}
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template <typename Method, bool has_null_map>
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void NO_INLINE Set::executeImplCase(
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Method & method,
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const ColumnRawPtrs & key_columns,
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ColumnUInt8::Container & vec_res,
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bool negative,
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size_t rows,
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ConstNullMapPtr null_map) const
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{
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Arena pool;
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typename Method::State state(key_columns, key_sizes, nullptr);
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/// NOTE Optimization is not used for consecutive identical strings.
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/// For all rows
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for (size_t i = 0; i < rows; ++i)
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{
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if (has_null_map && (*null_map)[i])
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{
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vec_res[i] = negative;
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}
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else
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{
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auto find_result = state.findKey(method.data, i, pool);
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vec_res[i] = negative ^ find_result.isFound();
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}
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}
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}
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void Set::executeOrdinary(
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const ColumnRawPtrs & key_columns,
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ColumnUInt8::Container & vec_res,
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bool negative,
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ConstNullMapPtr null_map) const
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{
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size_t rows = key_columns[0]->size();
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switch (data.type)
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{
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case SetVariants::Type::EMPTY:
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break;
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#define M(NAME) \
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case SetVariants::Type::NAME: \
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executeImpl(*data.NAME, key_columns, vec_res, negative, rows, null_map); \
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break;
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APPLY_FOR_SET_VARIANTS(M)
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#undef M
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}
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}
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void Set::checkColumnsNumber(size_t num_key_columns) const
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{
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if (data_types.size() != num_key_columns)
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{
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throw Exception(ErrorCodes::NUMBER_OF_COLUMNS_DOESNT_MATCH,
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"Number of columns in section IN doesn't match. {} at left, {} at right.",
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num_key_columns, data_types.size());
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}
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}
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bool Set::areTypesEqual(size_t set_type_idx, const DataTypePtr & other_type) const
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{
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/// Out-of-bound access can happen when same set expression built with different columns.
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/// Caller may call this method to make sure that the set is indeed the one they want
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/// without awaring data_types.size().
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if (set_type_idx >= data_types.size())
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return false;
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return removeNullable(recursiveRemoveLowCardinality(data_types[set_type_idx]))
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->equals(*removeNullable(recursiveRemoveLowCardinality(other_type)));
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}
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void Set::checkTypesEqual(size_t set_type_idx, const DataTypePtr & other_type) const
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{
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if (!this->areTypesEqual(set_type_idx, other_type))
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throw Exception("Types of column " + toString(set_type_idx + 1) + " in section IN don't match: "
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+ other_type->getName() + " on the left, "
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+ data_types[set_type_idx]->getName() + " on the right", ErrorCodes::TYPE_MISMATCH);
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}
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MergeTreeSetIndex::MergeTreeSetIndex(const Columns & set_elements, std::vector<KeyTuplePositionMapping> && indexes_mapping_)
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: has_all_keys(set_elements.size() == indexes_mapping_.size()), indexes_mapping(std::move(indexes_mapping_))
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{
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::sort(indexes_mapping.begin(), indexes_mapping.end(),
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[](const KeyTuplePositionMapping & l, const KeyTuplePositionMapping & r)
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{
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return std::tie(l.key_index, l.tuple_index) < std::tie(r.key_index, r.tuple_index);
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});
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indexes_mapping.erase(std::unique(
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indexes_mapping.begin(), indexes_mapping.end(),
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[](const KeyTuplePositionMapping & l, const KeyTuplePositionMapping & r)
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{
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return l.key_index == r.key_index;
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}), indexes_mapping.end());
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size_t tuple_size = indexes_mapping.size();
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ordered_set.resize(tuple_size);
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for (size_t i = 0; i < tuple_size; ++i)
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ordered_set[i] = set_elements[indexes_mapping[i].tuple_index];
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Block block_to_sort;
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SortDescription sort_description;
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for (size_t i = 0; i < tuple_size; ++i)
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{
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String column_name = "_" + toString(i);
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block_to_sort.insert({ordered_set[i], nullptr, column_name});
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sort_description.emplace_back(column_name, 1, 1);
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}
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sortBlock(block_to_sort, sort_description);
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for (size_t i = 0; i < tuple_size; ++i)
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ordered_set[i] = block_to_sort.getByPosition(i).column;
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}
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/** Return the BoolMask where:
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* 1: the intersection of the set and the range is non-empty
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* 2: the range contains elements not in the set
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*/
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BoolMask MergeTreeSetIndex::checkInRange(const std::vector<Range> & key_ranges, const DataTypes & data_types, bool single_point) const
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{
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size_t tuple_size = indexes_mapping.size();
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FieldValues left_point;
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FieldValues right_point;
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left_point.reserve(tuple_size);
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right_point.reserve(tuple_size);
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for (size_t i = 0; i < tuple_size; ++i)
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{
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left_point.emplace_back(ordered_set[i]->cloneEmpty());
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right_point.emplace_back(ordered_set[i]->cloneEmpty());
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}
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bool left_included = true;
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bool right_included = true;
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for (size_t i = 0; i < tuple_size; ++i)
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{
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std::optional<Range> new_range = KeyCondition::applyMonotonicFunctionsChainToRange(
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key_ranges[indexes_mapping[i].key_index],
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indexes_mapping[i].functions,
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data_types[indexes_mapping[i].key_index],
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single_point);
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if (!new_range)
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return {true, true};
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left_point[i].update(new_range->left);
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left_included &= new_range->left_included;
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right_point[i].update(new_range->right);
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right_included &= new_range->right_included;
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}
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/// lhs < rhs return -1
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/// lhs == rhs return 0
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/// lhs > rhs return 1
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auto compare = [](const IColumn & lhs, const FieldValue & rhs, size_t row)
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{
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if (rhs.isNegativeInfinity())
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return 1;
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if (rhs.isPositiveInfinity())
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{
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Field f;
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lhs.get(row, f);
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if (f.isNull())
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return 0; // +Inf == +Inf
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else
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return -1;
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}
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return lhs.compareAt(row, 0, *rhs.column, 1);
|
|
};
|
|
|
|
auto less = [this, &compare, tuple_size](size_t row, const auto & point)
|
|
{
|
|
for (size_t i = 0; i < tuple_size; ++i)
|
|
{
|
|
int res = compare(*ordered_set[i], point[i], row);
|
|
if (res)
|
|
return res < 0;
|
|
}
|
|
return false;
|
|
};
|
|
|
|
auto equals = [this, &compare, tuple_size](size_t row, const auto & point)
|
|
{
|
|
for (size_t i = 0; i < tuple_size; ++i)
|
|
if (compare(*ordered_set[i], point[i], row) != 0)
|
|
return false;
|
|
return true;
|
|
};
|
|
|
|
/** Because each hyperrectangle maps to a contiguous sequence of elements
|
|
* laid out in the lexicographically increasing order, the set intersects the range
|
|
* if and only if either bound coincides with an element or at least one element
|
|
* is between the lower bounds
|
|
*/
|
|
auto indices = collections::range(0, size());
|
|
auto left_lower = std::lower_bound(indices.begin(), indices.end(), left_point, less);
|
|
auto right_lower = std::lower_bound(indices.begin(), indices.end(), right_point, less);
|
|
|
|
/// A special case of 1-element KeyRange. It's useful for partition pruning.
|
|
bool one_element_range = true;
|
|
for (size_t i = 0; i < tuple_size; ++i)
|
|
{
|
|
auto & left = left_point[i];
|
|
auto & right = right_point[i];
|
|
if (left.isNormal() && right.isNormal())
|
|
{
|
|
if (0 != left.column->compareAt(0, 0, *right.column, 1))
|
|
{
|
|
one_element_range = false;
|
|
break;
|
|
}
|
|
}
|
|
else if ((left.isPositiveInfinity() && right.isPositiveInfinity()) || (left.isNegativeInfinity() && right.isNegativeInfinity()))
|
|
{
|
|
/// Special value equality.
|
|
}
|
|
else
|
|
{
|
|
one_element_range = false;
|
|
break;
|
|
}
|
|
}
|
|
if (one_element_range && has_all_keys)
|
|
{
|
|
/// Here we know that there is one element in range.
|
|
/// The main difference with the normal case is that we can definitely say that
|
|
/// condition in this range is always TRUE (can_be_false = 0) or always FALSE (can_be_true = 0).
|
|
|
|
/// Check if it's an empty range
|
|
if (!left_included || !right_included)
|
|
return {false, true};
|
|
else if (left_lower != indices.end() && equals(*left_lower, left_point))
|
|
return {true, false};
|
|
else
|
|
return {false, true};
|
|
}
|
|
|
|
/// If there are more than one element in the range, it can always be false. Thus we only need to check if it may be true or not.
|
|
/// Given left_lower >= left_point, right_lower >= right_point, find if there may be a match in between left_lower and right_lower.
|
|
if (left_lower + 1 < right_lower)
|
|
{
|
|
/// There is an point in between: left_lower + 1
|
|
return {true, true};
|
|
}
|
|
else if (left_lower + 1 == right_lower)
|
|
{
|
|
/// Need to check if left_lower is a valid match, as left_point <= left_lower < right_point <= right_lower.
|
|
/// Note: left_lower is valid.
|
|
if (left_included || !equals(*left_lower, left_point))
|
|
return {true, true};
|
|
|
|
/// We are unlucky that left_point fails to cover a point. Now we need to check if right_point can cover right_lower.
|
|
/// Check if there is a match at the right boundary.
|
|
return {right_included && right_lower != indices.end() && equals(*right_lower, right_point), true};
|
|
}
|
|
else // left_lower == right_lower
|
|
{
|
|
/// Need to check if right_point is a valid match, as left_point < right_point <= left_lower = right_lower.
|
|
/// Check if there is a match at the left boundary.
|
|
return {right_included && right_lower != indices.end() && equals(*right_lower, right_point), true};
|
|
}
|
|
}
|
|
|
|
bool MergeTreeSetIndex::hasMonotonicFunctionsChain() const
|
|
{
|
|
for (const auto & mapping : indexes_mapping)
|
|
if (!mapping.functions.empty())
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
void FieldValue::update(const Field & x)
|
|
{
|
|
if (x.isNegativeInfinity() || x.isPositiveInfinity())
|
|
value = x;
|
|
else
|
|
{
|
|
/// Keep at most one element in column.
|
|
if (!column->empty())
|
|
column->popBack(1);
|
|
column->insert(x);
|
|
value = Field(); // Set back to normal value.
|
|
}
|
|
}
|
|
|
|
}
|