1 | #pragma once |
2 | |
3 | #include <ext/shared_ptr_helper.h> |
4 | |
5 | #include <Storages/StorageSet.h> |
6 | #include <Parsers/ASTTablesInSelectQuery.h> |
7 | |
8 | |
9 | namespace DB |
10 | { |
11 | |
12 | class AnalyzedJoin; |
13 | class Join; |
14 | using HashJoinPtr = std::shared_ptr<Join>; |
15 | |
16 | |
17 | /** Allows you save the state for later use on the right side of the JOIN. |
18 | * When inserted into a table, the data will be inserted into the state, |
19 | * and also written to the backup file, to restore after the restart. |
20 | * Reading from the table is not possible directly - only specifying on the right side of JOIN is possible. |
21 | * |
22 | * When using, JOIN must be of the appropriate type (ANY|ALL LEFT|INNER ...). |
23 | */ |
24 | class StorageJoin : public ext::shared_ptr_helper<StorageJoin>, public StorageSetOrJoinBase |
25 | { |
26 | friend struct ext::shared_ptr_helper<StorageJoin>; |
27 | public: |
28 | String getName() const override { return "Join" ; } |
29 | |
30 | void truncate(const ASTPtr &, const Context &, TableStructureWriteLockHolder &) override; |
31 | |
32 | /// Access the innards. |
33 | HashJoinPtr & getJoin() { return join; } |
34 | HashJoinPtr getJoin(std::shared_ptr<AnalyzedJoin> analyzed_join) const; |
35 | |
36 | /// Verify that the data structure is suitable for implementing this type of JOIN. |
37 | void assertCompatible(ASTTableJoin::Kind kind_, ASTTableJoin::Strictness strictness_) const; |
38 | |
39 | BlockInputStreams read( |
40 | const Names & column_names, |
41 | const SelectQueryInfo & query_info, |
42 | const Context & context, |
43 | QueryProcessingStage::Enum processed_stage, |
44 | size_t max_block_size, |
45 | unsigned num_streams) override; |
46 | |
47 | private: |
48 | Block sample_block; |
49 | const Names key_names; |
50 | bool use_nulls; |
51 | SizeLimits limits; |
52 | ASTTableJoin::Kind kind; /// LEFT | INNER ... |
53 | ASTTableJoin::Strictness strictness; /// ANY | ALL |
54 | |
55 | std::shared_ptr<AnalyzedJoin> table_join; |
56 | HashJoinPtr join; |
57 | |
58 | void insertBlock(const Block & block) override; |
59 | void finishInsert() override {} |
60 | size_t getSize() const override; |
61 | |
62 | protected: |
63 | StorageJoin( |
64 | const String & relative_path_, |
65 | const String & database_name_, |
66 | const String & table_name_, |
67 | const Names & key_names_, |
68 | bool use_nulls_, |
69 | SizeLimits limits_, |
70 | ASTTableJoin::Kind kind_, ASTTableJoin::Strictness strictness_, |
71 | const ColumnsDescription & columns_, |
72 | const ConstraintsDescription & constraints_, |
73 | bool overwrite, |
74 | const Context & context_); |
75 | }; |
76 | |
77 | } |
78 | |