mariadb/sql/event_data_objects.h

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#ifndef _EVENT_DATA_OBJECTS_H_
#define _EVENT_DATA_OBJECTS_H_
/* Copyright (C) 2004-2006 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/**
@addtogroup Event_Scheduler
@{
@file event_data_objects.h
*/
#include "event_parse_data.h"
#include "thr_lock.h" /* thr_lock_type */
class Field;
class THD;
class Time_zone;
struct TABLE;
class Event_queue_element_for_exec
{
public:
Event_queue_element_for_exec(){};
~Event_queue_element_for_exec();
bool
init(LEX_STRING dbname, LEX_STRING name);
LEX_STRING dbname;
LEX_STRING name;
bool dropped;
THD *thd;
private:
/* Prevent use of these */
Event_queue_element_for_exec(const Event_queue_element_for_exec &);
void operator=(Event_queue_element_for_exec &);
};
class Event_basic
{
protected:
MEM_ROOT mem_root;
public:
LEX_STRING dbname;
LEX_STRING name;
LEX_STRING definer;// combination of user and host
Time_zone *time_zone;
Event_basic();
virtual ~Event_basic();
virtual bool
load_from_row(THD *thd, TABLE *table) = 0;
protected:
bool
load_string_fields(Field **fields, ...);
bool
load_time_zone(THD *thd, const LEX_STRING tz_name);
};
class Event_queue_element : public Event_basic
{
protected:
bool status_changed;
bool last_executed_changed;
public:
int on_completion;
int status;
longlong originator;
my_time_t last_executed;
my_time_t execute_at;
my_time_t starts;
my_time_t ends;
my_bool starts_null;
my_bool ends_null;
my_bool execute_at_null;
longlong expression;
interval_type interval;
bool dropped;
uint execution_count;
Event_queue_element();
virtual ~Event_queue_element();
virtual bool
load_from_row(THD *thd, TABLE *table);
bool
compute_next_execution_time();
void
mark_last_executed(THD *thd);
bool
update_timing_fields(THD *thd);
};
class Event_timed : public Event_queue_element
{
Event_timed(const Event_timed &); /* Prevent use of these */
void operator=(Event_timed &);
public:
LEX_STRING body;
LEX_STRING definer_user;
LEX_STRING definer_host;
LEX_STRING comment;
ulonglong created;
ulonglong modified;
ulong sql_mode;
Patch for the following bugs: - BUG#11986: Stored routines and triggers can fail if the code has a non-ascii symbol - BUG#16291: mysqldump corrupts string-constants with non-ascii-chars - BUG#19443: INFORMATION_SCHEMA does not support charsets properly - BUG#21249: Character set of SP-var can be ignored - BUG#25212: Character set of string constant is ignored (stored routines) - BUG#25221: Character set of string constant is ignored (triggers) There were a few general problems that caused these bugs: 1. Character set information of the original (definition) query for views, triggers, stored routines and events was lost. 2. mysqldump output query in client character set, which can be inappropriate to encode definition-query. 3. INFORMATION_SCHEMA used strings with mixed encodings to display object definition; 1. No query-definition-character set. In order to compile query into execution code, some extra data (such as environment variables or the database character set) is used. The problem here was that this context was not preserved. So, on the next load it can differ from the original one, thus the result will be different. The context contains the following data: - client character set; - connection collation (character set and collation); - collation of the owner database; The fix is to store this context and use it each time we parse (compile) and execute the object (stored routine, trigger, ...). 2. Wrong mysqldump-output. The original query can contain several encodings (by means of character set introducers). The problem here was that we tried to convert original query to the mysqldump-client character set. Moreover, we stored queries in different character sets for different objects (views, for one, used UTF8, triggers used original character set). The solution is - to store definition queries in the original character set; - to change SHOW CREATE statement to output definition query in the binary character set (i.e. without any conversion); - introduce SHOW CREATE TRIGGER statement; - to dump special statements to switch the context to the original one before dumping and restore it afterwards. Note, in order to preserve the database collation at the creation time, additional ALTER DATABASE might be used (to temporary switch the database collation back to the original value). In this case, ALTER DATABASE privilege will be required. This is a backward-incompatible change. 3. INFORMATION_SCHEMA showed non-UTF8 strings The fix is to generate UTF8-query during the parsing, store it in the object and show it in the INFORMATION_SCHEMA. Basically, the idea is to create a copy of the original query convert it to UTF8. Character set introducers are removed and all text literals are converted to UTF8. This UTF8 query is intended to provide user-readable output. It must not be used to recreate the object. Specialized SHOW CREATE statements should be used for this. The reason for this limitation is the following: the original query can contain symbols from several character sets (by means of character set introducers). Example: - original query: CREATE VIEW v1 AS SELECT _cp1251 'Hello' AS c1; - UTF8 query (for INFORMATION_SCHEMA): CREATE VIEW v1 AS SELECT 'Hello' AS c1;
2007-06-28 19:34:54 +02:00
class Stored_program_creation_ctx *creation_ctx;
LEX_STRING body_utf8;
Event_timed();
virtual ~Event_timed();
void
init();
virtual bool
load_from_row(THD *thd, TABLE *table);
int
get_create_event(THD *thd, String *buf);
};
class Event_job_data : public Event_basic
{
public:
LEX_STRING body;
LEX_STRING definer_user;
LEX_STRING definer_host;
ulong sql_mode;
Patch for the following bugs: - BUG#11986: Stored routines and triggers can fail if the code has a non-ascii symbol - BUG#16291: mysqldump corrupts string-constants with non-ascii-chars - BUG#19443: INFORMATION_SCHEMA does not support charsets properly - BUG#21249: Character set of SP-var can be ignored - BUG#25212: Character set of string constant is ignored (stored routines) - BUG#25221: Character set of string constant is ignored (triggers) There were a few general problems that caused these bugs: 1. Character set information of the original (definition) query for views, triggers, stored routines and events was lost. 2. mysqldump output query in client character set, which can be inappropriate to encode definition-query. 3. INFORMATION_SCHEMA used strings with mixed encodings to display object definition; 1. No query-definition-character set. In order to compile query into execution code, some extra data (such as environment variables or the database character set) is used. The problem here was that this context was not preserved. So, on the next load it can differ from the original one, thus the result will be different. The context contains the following data: - client character set; - connection collation (character set and collation); - collation of the owner database; The fix is to store this context and use it each time we parse (compile) and execute the object (stored routine, trigger, ...). 2. Wrong mysqldump-output. The original query can contain several encodings (by means of character set introducers). The problem here was that we tried to convert original query to the mysqldump-client character set. Moreover, we stored queries in different character sets for different objects (views, for one, used UTF8, triggers used original character set). The solution is - to store definition queries in the original character set; - to change SHOW CREATE statement to output definition query in the binary character set (i.e. without any conversion); - introduce SHOW CREATE TRIGGER statement; - to dump special statements to switch the context to the original one before dumping and restore it afterwards. Note, in order to preserve the database collation at the creation time, additional ALTER DATABASE might be used (to temporary switch the database collation back to the original value). In this case, ALTER DATABASE privilege will be required. This is a backward-incompatible change. 3. INFORMATION_SCHEMA showed non-UTF8 strings The fix is to generate UTF8-query during the parsing, store it in the object and show it in the INFORMATION_SCHEMA. Basically, the idea is to create a copy of the original query convert it to UTF8. Character set introducers are removed and all text literals are converted to UTF8. This UTF8 query is intended to provide user-readable output. It must not be used to recreate the object. Specialized SHOW CREATE statements should be used for this. The reason for this limitation is the following: the original query can contain symbols from several character sets (by means of character set introducers). Example: - original query: CREATE VIEW v1 AS SELECT _cp1251 'Hello' AS c1; - UTF8 query (for INFORMATION_SCHEMA): CREATE VIEW v1 AS SELECT 'Hello' AS c1;
2007-06-28 19:34:54 +02:00
class Stored_program_creation_ctx *creation_ctx;
Event_job_data();
virtual bool
load_from_row(THD *thd, TABLE *table);
bool
execute(THD *thd, bool drop);
private:
bool
construct_sp_sql(THD *thd, String *sp_sql);
bool
construct_drop_event_sql(THD *thd, String *sp_sql);
Event_job_data(const Event_job_data &); /* Prevent use of these */
void operator=(Event_job_data &);
};
/* Compares only the schema part of the identifier */
bool
event_basic_db_equal(LEX_STRING db, Event_basic *et);
/* Compares the whole identifier*/
bool
event_basic_identifier_equal(LEX_STRING db, LEX_STRING name, Event_basic *b);
/**
@} (End of group Event_Scheduler)
*/
#endif /* _EVENT_DATA_OBJECTS_H_ */