libdballe  9.11
sql.h
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1 
4 #ifndef DBALLE_SQL_H
5 #define DBALLE_SQL_H
6 
7 #include <dballe/core/error.h>
8 #include <dballe/fwd.h>
9 #include <dballe/sql/fwd.h>
10 #include <string>
11 #include <memory>
12 
14 #undef USE_REF_INT
15 
20 // #define TRACE_DB
21 
22 #ifdef TRACE_DB
23 #define TRACE(...) fprintf(stderr, __VA_ARGS__)
24 #define IFTRACE if (1)
25 #else
26 
27 #define TRACE(...) do { } while (0)
28 
29 #define IFTRACE if (0)
30 #endif
31 
34 namespace dballe {
35 class Datetime;
36 
37 namespace sql {
38 
40 enum class ServerType
41 {
42  MYSQL,
43  SQLITE,
44  ORACLE,
45  POSTGRES,
46 };
47 
49 const char* format_server_type(ServerType type);
50 
51 
52 class Connection : public std::enable_shared_from_this<Connection>
53 {
54 private:
55  static void atfork_prepare_hook();
56  static void atfork_parent_hook();
57  static void atfork_child_hook();
58 
59 protected:
60  std::string url;
61 
62  Connection();
63 
65  void register_atfork();
66 
67  // Optional pthread_atfork hooks
68  virtual void fork_prepare();
69  virtual void fork_parent();
70  virtual void fork_child();
71 
72 public:
80 
81  virtual ~Connection();
82 
83  const std::string& get_url() const { return url; }
84 
91  virtual std::unique_ptr<Transaction> transaction(bool readonly=false) = 0;
92 
94  virtual bool has_table(const std::string& name) = 0;
95 
101  virtual std::string get_setting(const std::string& key) = 0;
102 
108  virtual void set_setting(const std::string& key, const std::string& value) = 0;
109 
111  virtual void drop_settings() = 0;
112 
114  virtual void add_datetime(Querybuf& qb, const Datetime& dt) const;
115 
117  virtual void execute(const std::string& query) = 0;
118 
120  virtual void explain(const std::string& query, FILE* out) = 0;
121 
123  static std::shared_ptr<Connection> create(const DBConnectOptions& options);
124 };
125 
136 {
137 public:
138  Transaction() {}
139  Transaction(const Transaction&) = delete;
140  Transaction& operator=(const Transaction&) = delete;
141  virtual ~Transaction();
142 
144  virtual void commit() = 0;
145 
147  virtual void rollback() = 0;
148 
150  virtual void rollback_nothrow() noexcept = 0;
151 
154  virtual void lock_table(const char* name) = 0;
155 };
156 
157 }
158 }
159 
160 #endif
Forward declarations for public dballe/sql names.
virtual void rollback_nothrow() noexcept=0
Roll back this transaction.
ServerType server_type
Type of SQL server we are connected to.
Definition: sql.h:79
Definition: cmdline.h:18
virtual std::unique_ptr< Transaction > transaction(bool readonly=false)=0
Begin a transaction.
virtual void set_setting(const std::string &key, const std::string &value)=0
Set a value in the settings table.
virtual void add_datetime(Querybuf &qb, const Datetime &dt) const
Format a datetime and add it to the querybuf.
Definition: sql.h:52
ServerType
Supported SQL servers.
Definition: sql.h:40
virtual void commit()=0
Commit this transaction.
virtual void rollback()=0
Roll back this transaction.
virtual void drop_settings()=0
Drop the settings table.
void register_atfork()
Register this connection to be notified in case of fork()-ing.
A RAII transaction interface for SQL transactions.
Definition: sql.h:135
virtual std::string get_setting(const std::string &key)=0
Get a value from the settings table.
Date and time.
Definition: types.h:164
virtual bool has_table(const std::string &name)=0
Check if the database contains a table.
virtual void execute(const std::string &query)=0
Execute a query without reading its results.
virtual void explain(const std::string &query, FILE *out)=0
Format and print the EXPLAIN output for the query to the given file.
Options controlling how to connect to a database.
Definition: db.h:17
virtual void lock_table(const char *name)=0
Get an exclusive lock on the given table until the end of the transaction.
String buffer for composing database queries.
Definition: querybuf.h:15
static std::shared_ptr< Connection > create(const DBConnectOptions &options)
Create a new connection from a URL.