1 | #pragma once |
2 | |
3 | #include "config_core.h" |
4 | #if USE_MYSQL |
5 | |
6 | #include <mysqlxx/Pool.h> |
7 | #include <Databases/DatabasesCommon.h> |
8 | #include <Interpreters/Context.h> |
9 | #include <memory> |
10 | #include <Parsers/ASTCreateQuery.h> |
11 | |
12 | |
13 | namespace DB |
14 | { |
15 | |
16 | /** Real-time access to table list and table structure from remote MySQL |
17 | * It doesn't make any manipulations with filesystem. |
18 | * All tables are created by calling code after real-time pull-out structure from remote MySQL |
19 | */ |
20 | class DatabaseMySQL : public IDatabase |
21 | { |
22 | public: |
23 | ~DatabaseMySQL() override; |
24 | |
25 | DatabaseMySQL( |
26 | const Context & global_context, const String & database_name, const String & metadata_path, |
27 | const ASTStorage * database_engine_define, const String & database_name_in_mysql, mysqlxx::Pool && pool); |
28 | |
29 | String getEngineName() const override { return "MySQL" ; } |
30 | |
31 | bool empty(const Context & context) const override; |
32 | |
33 | DatabaseTablesIteratorPtr getTablesIterator(const Context & context, const FilterByNameFunction & filter_by_table_name = {}) override; |
34 | |
35 | ASTPtr getCreateDatabaseQuery() const override; |
36 | |
37 | bool isTableExist(const Context & context, const String & name) const override; |
38 | |
39 | StoragePtr tryGetTable(const Context & context, const String & name) const override; |
40 | |
41 | time_t getObjectMetadataModificationTime(const String & name) const override; |
42 | |
43 | void shutdown() override; |
44 | |
45 | void drop(const Context & /*context*/) override; |
46 | |
47 | String getMetadataPath() const override; |
48 | |
49 | void createTable(const Context &, const String & table_name, const StoragePtr & storage, const ASTPtr & create_query) override; |
50 | |
51 | void loadStoredObjects(Context &, bool) override; |
52 | |
53 | StoragePtr detachTable(const String & table_name) override; |
54 | |
55 | void removeTable(const Context &, const String & table_name) override; |
56 | |
57 | void attachTable(const String & table_name, const StoragePtr & storage) override; |
58 | |
59 | |
60 | protected: |
61 | ASTPtr getCreateTableQueryImpl(const Context & context, const String & name, bool throw_on_error) const override; |
62 | |
63 | private: |
64 | Context global_context; |
65 | String metadata_path; |
66 | ASTPtr database_engine_define; |
67 | String database_name_in_mysql; |
68 | |
69 | mutable std::mutex mutex; |
70 | std::atomic<bool> quit{false}; |
71 | std::condition_variable cond; |
72 | |
73 | using MySQLPool = mysqlxx::Pool; |
74 | using ModifyTimeAndStorage = std::pair<UInt64, StoragePtr>; |
75 | |
76 | mutable MySQLPool mysql_pool; |
77 | mutable std::vector<StoragePtr> outdated_tables; |
78 | mutable std::map<String, ModifyTimeAndStorage> local_tables_cache; |
79 | |
80 | std::unordered_set<String> remove_or_detach_tables; |
81 | |
82 | void cleanOutdatedTables(); |
83 | |
84 | void fetchTablesIntoLocalCache() const; |
85 | |
86 | std::map<String, UInt64> fetchTablesWithModificationTime() const; |
87 | |
88 | std::map<String, NamesAndTypesList> fetchTablesColumnsList(const std::vector<String> & tables_name) const; |
89 | |
90 | void (const std::map<String, UInt64> & tables_with_modification_time) const; |
91 | |
92 | void fetchLatestTablesStructureIntoCache(const std::map<String, UInt64> & tables_modification_time) const; |
93 | |
94 | ThreadFromGlobalPool thread{&DatabaseMySQL::cleanOutdatedTables, this}; |
95 | }; |
96 | |
97 | } |
98 | |
99 | #endif |
100 | |