ClickHouse/src/Interpreters/join_common.h
Vladimir 576b407804
Support conditions in JOIN ON section (#24420)
* Try to enforce table identification in CollectJoinOnKeysMatcher

* Support filtering conditions in JOIN ON for HashJoin

* Correct handle non equi join

* Update test 00878_join_unexpected_results

* Join on filters calculated as one row before join

* Do not lookup key in hash join if condition for row is not hold

* better

* Support filtering conditions in JOIN ON for MergeJoin

* Support Nullable mask in JOIN ON section

* Fix style in Interpreters/TableJoin.cpp

* Change return type of getColumnAsMask in join_common to ColumnPtr

* Handle Nullable(Nothing) type in JOIN ON section, add test cases

* Fix type cast JoinCommon::getColumnAsMask

* Check type if conditions in JOIN ON section, support functions

* Update tests with JOIN ON

* Style changes, add comments for conditions in JOIN ON section

* Add test cases for join on condtions

* JOIN ON key1 = key2 AND (cond1 OR cond2)

* Remove CollectJoinOnKeysVisitor has_join_keys

* Add test cases for join on nullable/lc conditions

* Fix style

* Change error code 48 to 403 in join on tests

* Fix whitespace
2021-07-21 20:03:33 +03:00

105 lines
4.5 KiB
C++

#pragma once
#include <Columns/ColumnsNumber.h>
#include <Core/Block.h>
#include <Interpreters/IJoin.h>
#include <Interpreters/ActionsDAG.h>
#include <Interpreters/ExpressionActions.h>
namespace DB
{
struct ColumnWithTypeAndName;
class TableJoin;
class IColumn;
using ColumnRawPtrs = std::vector<const IColumn *>;
using UInt8ColumnDataPtr = const ColumnUInt8::Container *;
namespace JoinCommon
{
bool canBecomeNullable(const DataTypePtr & type);
DataTypePtr convertTypeToNullable(const DataTypePtr & type);
void convertColumnToNullable(ColumnWithTypeAndName & column, bool remove_low_card = false);
void convertColumnsToNullable(Block & block, size_t starting_pos = 0);
void removeColumnNullability(ColumnWithTypeAndName & column);
void changeColumnRepresentation(const ColumnPtr & src_column, ColumnPtr & dst_column);
ColumnPtr emptyNotNullableClone(const ColumnPtr & column);
ColumnPtr materializeColumn(const Block & block, const String & name);
Columns materializeColumns(const Block & block, const Names & names);
ColumnRawPtrs materializeColumnsInplace(Block & block, const Names & names);
ColumnRawPtrs getRawPointers(const Columns & columns);
void removeLowCardinalityInplace(Block & block);
void removeLowCardinalityInplace(Block & block, const Names & names, bool change_type = true);
void restoreLowCardinalityInplace(Block & block);
ColumnRawPtrs extractKeysForJoin(const Block & block_keys, const Names & key_names_right);
/// Throw an exception if join condition column is not UIint8
void checkTypesOfMasks(const Block & block_left, const String & condition_name_left,
const Block & block_right, const String & condition_name_right);
/// Throw an exception if blocks have different types of key columns . Compare up to Nullability.
void checkTypesOfKeys(const Block & block_left, const Names & key_names_left,
const Block & block_right, const Names & key_names_right);
/// Check both keys and conditions
void checkTypesOfKeys(const Block & block_left, const Names & key_names_left, const String & condition_name_left,
const Block & block_right, const Names & key_names_right, const String & condition_name_right);
void createMissedColumns(Block & block);
void joinTotals(Block left_totals, Block right_totals, const TableJoin & table_join, Block & out_block);
void addDefaultValues(IColumn & column, const DataTypePtr & type, size_t count);
bool typesEqualUpToNullability(DataTypePtr left_type, DataTypePtr right_type);
/// Return mask array of type ColumnUInt8 for specified column. Source should have type UInt8 or Nullable(UInt8).
ColumnPtr getColumnAsMask(const Block & block, const String & column_name);
/// Split key and other columns by keys name list
void splitAdditionalColumns(const Names & key_names, const Block & sample_block, Block & block_keys, Block & block_others);
void changeLowCardinalityInplace(ColumnWithTypeAndName & column);
}
/// Creates result from right table data in RIGHT and FULL JOIN when keys are not present in left table.
class NotJoined
{
public:
NotJoined(const TableJoin & table_join, const Block & saved_block_sample_, const Block & right_sample_block,
const Block & result_sample_block_, const Names & key_names_left_ = {}, const Names & key_names_right_ = {});
void correctLowcardAndNullability(MutableColumns & columns_right);
void addLeftColumns(Block & block, size_t rows_added) const;
void addRightColumns(Block & block, MutableColumns & columns_right) const;
void copySameKeys(Block & block) const;
protected:
Block saved_block_sample;
Block result_sample_block;
Names key_names_left;
Names key_names_right;
~NotJoined() = default;
private:
/// Indices of columns in result_sample_block that should be generated
std::vector<size_t> column_indices_left;
/// Indices of columns that come from the right-side table: right_pos -> result_pos
std::unordered_map<size_t, size_t> column_indices_right;
///
std::unordered_map<size_t, size_t> same_result_keys;
/// Which right columns (saved in parent) need nullability change before placing them in result block
std::vector<size_t> right_nullability_adds;
std::vector<size_t> right_nullability_removes;
/// Which right columns (saved in parent) need LowCardinality change before placing them in result block
std::vector<std::pair<size_t, ColumnPtr>> right_lowcard_changes;
void setRightIndex(size_t right_pos, size_t result_position);
void extractColumnChanges(size_t right_pos, size_t result_pos);
};
}