Loading storage/example/ha_example.h +150 −56 Original line number Diff line number Diff line Loading @@ -14,20 +14,31 @@ along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* Please read ha_exmple.cc before reading this file. Please keep in mind that the example storage engine implements all methods that are required to be implemented. handler.h has a full list of methods that you can implement. /** @file ha_example.h @brief The ha_example engine is a stubbed storage engine for example purposes only; it does nothing at this point. Its purpose is to provide a source code illustration of how to begin writing new storage engines; see also /storage/example/ha_example.cc. @note Please read ha_example.cc before reading this file. Reminder: The example storage engine implements all methods that are *required* to be implemented. For a full list of all methods that you can implement, see handler.h. @see /sql/handler.h and /storage/example/ha_example.cc */ #ifdef USE_PRAGMA_INTERFACE #pragma interface /* gcc class implementation */ #endif /* EXAMPLE_SHARE is a structure that will be shared amoung all open handlers The example implements the minimum of what you will probably need. /** @brief EXAMPLE_SHARE is a structure that will be shared among all open handlers. This example implements the minimum of what you will probably need. */ typedef struct st_example_share { char *table_name; Loading @@ -36,117 +47,200 @@ typedef struct st_example_share { THR_LOCK lock; } EXAMPLE_SHARE; /* /** @brief Class definition for the storage engine */ class ha_example: public handler { THR_LOCK_DATA lock; /* MySQL lock */ EXAMPLE_SHARE *share; /* Shared lock info */ THR_LOCK_DATA lock; ///< MySQL lock EXAMPLE_SHARE *share; ///< Shared lock info public: ha_example(handlerton *hton, TABLE_SHARE *table_arg); ~ha_example() { } /* The name that will be used for display purposes */ /** @brief The name that will be used for display purposes. */ const char *table_type() const { return "EXAMPLE"; } /* The name of the index type that will be used for display don't implement this method unless you really have indexes /** @brief The name of the index type that will be used for display. Don't implement this method unless you really have indexes. */ const char *index_type(uint inx) { return "HASH"; } /** @brief The file extensions. */ const char **bas_ext() const; /* This is a list of flags that says what the storage engine implements. The current table flags are documented in handler.h /** @brief This is a list of flags that indicate what functionality the storage engine implements. The current table flags are documented in handler.h */ ulonglong table_flags() const { return 0; } /* This is a bitmap of flags that says how the storage engine /** @brief This is a bitmap of flags that indicates how the storage engine implements indexes. The current index flags are documented in handler.h. If you do not implement indexes, just return zero here. handler.h. If you do not implement indexes, just return zero here. part is the key part to check. First key part is 0 If all_parts it's set, MySQL want to know the flags for the combined index up to and including 'part'. @details part is the key part to check. First key part is 0. If all_parts is set, MySQL wants to know the flags for the combined index, up to and including 'part'. */ ulong index_flags(uint inx, uint part, bool all_parts) const { return 0; } /* unireg.cc will call the following to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here. MySQL will do min(your_limits, MySQL_limits) automatically There is no need to implement ..._key_... methods if you don't suport indexes. /** @brief unireg.cc will call max_supported_record_length(), max_supported_keys(), max_supported_key_parts(), uint max_supported_key_length() to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. */ uint max_supported_record_length() const { return HA_MAX_REC_LENGTH; } /** @brief unireg.cc will call this to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. @details There is no need to implement ..._key_... methods if your engine doesn't support indexes. */ uint max_supported_keys() const { return 0; } /** @brief unireg.cc will call this to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. @details There is no need to implement ..._key_... methods if your engine doesn't support indexes. */ uint max_supported_key_parts() const { return 0; } /** @brief unireg.cc will call this to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. @details There is no need to implement ..._key_... methods if your engine doesn't support indexes. */ uint max_supported_key_length() const { return 0; } /* /** @brief Called in test_quick_select to determine if indexes should be used. */ virtual double scan_time() { return (double) (stats.records+stats.deleted) / 20.0+10; } /* The next method will never be called if you do not implement indexes. /** @brief This method will never be called if you do not implement indexes. */ virtual double read_time(ha_rows rows) { return (double) rows / 20.0+1; } /* Everything below are methods that we implment in ha_example.cc. Everything below are methods that we implement in ha_example.cc. Most of these methods are not obligatory, skip them and MySQL will treat them as not implemented */ /** @brief We implement this in ha_example.cc; it's a required method. */ int open(const char *name, int mode, uint test_if_locked); // required /** @brief We implement this in ha_example.cc; it's a required method. */ int close(void); // required /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int write_row(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int update_row(const byte * old_data, byte * new_data); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int delete_row(const byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_read(byte * buf, const byte * key, uint key_len, enum ha_rkey_function find_flag); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_next(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_prev(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_first(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_last(byte * buf); /* unlike index_init(), rnd_init() can be called two times without rnd_end() in between (it only makes sense if scan=1). then the second call should prepare for the new table scan (e.g if rnd_init allocates the cursor, second call should position it to the start of the table, no need to deallocate and allocate it again /** @brief Unlike index_init(), rnd_init() can be called two consecutive times without rnd_end() in between (it only makes sense if scan=1). In this case, the second call should prepare for the new table scan (e.g if rnd_init() allocates the cursor, the second call should position the cursor to the start of the table; no need to deallocate and allocate it again. This is a required method. */ int rnd_init(bool scan); //required int rnd_end(); int rnd_next(byte *buf); //required int rnd_pos(byte * buf, byte *pos); //required void position(const byte *record); //required int info(uint); //required int rnd_next(byte *buf); ///< required int rnd_pos(byte * buf, byte *pos); ///< required void position(const byte *record); ///< required int info(uint); ///< required int extra(enum ha_extra_function operation); int external_lock(THD *thd, int lock_type); //required int external_lock(THD *thd, int lock_type); ///< required int delete_all_rows(void); ha_rows records_in_range(uint inx, key_range *min_key, key_range *max_key); int delete_table(const char *from); int rename_table(const char * from, const char * to); int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info); //required HA_CREATE_INFO *create_info); ///< required THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to, enum thr_lock_type lock_type); //required }; enum thr_lock_type lock_type); ///< required Loading
storage/example/ha_example.h +150 −56 Original line number Diff line number Diff line Loading @@ -14,20 +14,31 @@ along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* Please read ha_exmple.cc before reading this file. Please keep in mind that the example storage engine implements all methods that are required to be implemented. handler.h has a full list of methods that you can implement. /** @file ha_example.h @brief The ha_example engine is a stubbed storage engine for example purposes only; it does nothing at this point. Its purpose is to provide a source code illustration of how to begin writing new storage engines; see also /storage/example/ha_example.cc. @note Please read ha_example.cc before reading this file. Reminder: The example storage engine implements all methods that are *required* to be implemented. For a full list of all methods that you can implement, see handler.h. @see /sql/handler.h and /storage/example/ha_example.cc */ #ifdef USE_PRAGMA_INTERFACE #pragma interface /* gcc class implementation */ #endif /* EXAMPLE_SHARE is a structure that will be shared amoung all open handlers The example implements the minimum of what you will probably need. /** @brief EXAMPLE_SHARE is a structure that will be shared among all open handlers. This example implements the minimum of what you will probably need. */ typedef struct st_example_share { char *table_name; Loading @@ -36,117 +47,200 @@ typedef struct st_example_share { THR_LOCK lock; } EXAMPLE_SHARE; /* /** @brief Class definition for the storage engine */ class ha_example: public handler { THR_LOCK_DATA lock; /* MySQL lock */ EXAMPLE_SHARE *share; /* Shared lock info */ THR_LOCK_DATA lock; ///< MySQL lock EXAMPLE_SHARE *share; ///< Shared lock info public: ha_example(handlerton *hton, TABLE_SHARE *table_arg); ~ha_example() { } /* The name that will be used for display purposes */ /** @brief The name that will be used for display purposes. */ const char *table_type() const { return "EXAMPLE"; } /* The name of the index type that will be used for display don't implement this method unless you really have indexes /** @brief The name of the index type that will be used for display. Don't implement this method unless you really have indexes. */ const char *index_type(uint inx) { return "HASH"; } /** @brief The file extensions. */ const char **bas_ext() const; /* This is a list of flags that says what the storage engine implements. The current table flags are documented in handler.h /** @brief This is a list of flags that indicate what functionality the storage engine implements. The current table flags are documented in handler.h */ ulonglong table_flags() const { return 0; } /* This is a bitmap of flags that says how the storage engine /** @brief This is a bitmap of flags that indicates how the storage engine implements indexes. The current index flags are documented in handler.h. If you do not implement indexes, just return zero here. handler.h. If you do not implement indexes, just return zero here. part is the key part to check. First key part is 0 If all_parts it's set, MySQL want to know the flags for the combined index up to and including 'part'. @details part is the key part to check. First key part is 0. If all_parts is set, MySQL wants to know the flags for the combined index, up to and including 'part'. */ ulong index_flags(uint inx, uint part, bool all_parts) const { return 0; } /* unireg.cc will call the following to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here. MySQL will do min(your_limits, MySQL_limits) automatically There is no need to implement ..._key_... methods if you don't suport indexes. /** @brief unireg.cc will call max_supported_record_length(), max_supported_keys(), max_supported_key_parts(), uint max_supported_key_length() to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. */ uint max_supported_record_length() const { return HA_MAX_REC_LENGTH; } /** @brief unireg.cc will call this to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. @details There is no need to implement ..._key_... methods if your engine doesn't support indexes. */ uint max_supported_keys() const { return 0; } /** @brief unireg.cc will call this to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. @details There is no need to implement ..._key_... methods if your engine doesn't support indexes. */ uint max_supported_key_parts() const { return 0; } /** @brief unireg.cc will call this to make sure that the storage engine can handle the data it is about to send. Return *real* limits of your storage engine here; MySQL will do min(your_limits, MySQL_limits) automatically. @details There is no need to implement ..._key_... methods if your engine doesn't support indexes. */ uint max_supported_key_length() const { return 0; } /* /** @brief Called in test_quick_select to determine if indexes should be used. */ virtual double scan_time() { return (double) (stats.records+stats.deleted) / 20.0+10; } /* The next method will never be called if you do not implement indexes. /** @brief This method will never be called if you do not implement indexes. */ virtual double read_time(ha_rows rows) { return (double) rows / 20.0+1; } /* Everything below are methods that we implment in ha_example.cc. Everything below are methods that we implement in ha_example.cc. Most of these methods are not obligatory, skip them and MySQL will treat them as not implemented */ /** @brief We implement this in ha_example.cc; it's a required method. */ int open(const char *name, int mode, uint test_if_locked); // required /** @brief We implement this in ha_example.cc; it's a required method. */ int close(void); // required /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int write_row(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int update_row(const byte * old_data, byte * new_data); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int delete_row(const byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_read(byte * buf, const byte * key, uint key_len, enum ha_rkey_function find_flag); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_next(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_prev(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_first(byte * buf); /** @brief We implement this in ha_example.cc. It's not an obligatory method; skip it and and MySQL will treat it as not implemented. */ int index_last(byte * buf); /* unlike index_init(), rnd_init() can be called two times without rnd_end() in between (it only makes sense if scan=1). then the second call should prepare for the new table scan (e.g if rnd_init allocates the cursor, second call should position it to the start of the table, no need to deallocate and allocate it again /** @brief Unlike index_init(), rnd_init() can be called two consecutive times without rnd_end() in between (it only makes sense if scan=1). In this case, the second call should prepare for the new table scan (e.g if rnd_init() allocates the cursor, the second call should position the cursor to the start of the table; no need to deallocate and allocate it again. This is a required method. */ int rnd_init(bool scan); //required int rnd_end(); int rnd_next(byte *buf); //required int rnd_pos(byte * buf, byte *pos); //required void position(const byte *record); //required int info(uint); //required int rnd_next(byte *buf); ///< required int rnd_pos(byte * buf, byte *pos); ///< required void position(const byte *record); ///< required int info(uint); ///< required int extra(enum ha_extra_function operation); int external_lock(THD *thd, int lock_type); //required int external_lock(THD *thd, int lock_type); ///< required int delete_all_rows(void); ha_rows records_in_range(uint inx, key_range *min_key, key_range *max_key); int delete_table(const char *from); int rename_table(const char * from, const char * to); int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info); //required HA_CREATE_INFO *create_info); ///< required THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to, enum thr_lock_type lock_type); //required }; enum thr_lock_type lock_type); ///< required
