mariadb/sql/event_db_repository.h
unknown 086fba7627 BUG#16420: Events: timestamps become UTC
BUG#26429: SHOW CREATE EVENT is incorrect for an event that
           STARTS NOW()
BUG#26431: Impossible to re-create an event from backup if its
           STARTS clause is in the past
WL#3698: Events: execution in local time zone

The problem was that local times specified by the user in AT, STARTS
and ENDS of CREATE EVENT/ALTER EVENT statement were converted to UTC,
and the original time zone was forgotten.  This way, event scheduler
couldn't honor Daylight Saving Time shifts, and times shown to the
user were also in UTC.  Additionally, CREATE EVENT didn't allow times
in the past, thus preventing straightforward event restoration from
old backups.

This patch reworks event scheduler time computations, performing them
in the time zone associated with the event.  Also it allows times to
be in the past.

The patch adds time_zone column to mysql.event table.

NOTE: The patch is almost final, but the bug#9953 should be pushed
first.


client/mysqldump.c:
  Before every CREATE EVENT, output its time zone.
mysql-test/include/wait_condition.inc:
  Add optional $wait_timeout parameter.
mysql-test/lib/init_db.sql:
  Add time_zone column.
mysql-test/r/events.result:
  Update result.
mysql-test/r/events_bugs.result:
  Update result.
mysql-test/r/events_grant.result:
  Update result.
mysql-test/r/events_restart_phase1.result:
  Update result.
mysql-test/r/events_scheduling.result:
  Update result.
mysql-test/r/mysqldump.result:
  Update result.
mysql-test/r/ps.result:
  Update result.
mysql-test/r/system_mysql_db.result:
  Update result.
mysql-test/t/events.test:
  Remove STARTS from the result, as it depends on current time.
mysql-test/t/events_bugs.test:
  Time in the past is no longer an error.
mysql-test/t/events_restart_phase1.test:
  Fill new column 'time_zone' in mysql.event.
mysql-test/t/events_scheduling.test:
  Cleanup: disable event scheduler.
scripts/mysql_create_system_tables.sh:
  Add new column 'time_zone' to mysql.event.
scripts/mysql_fix_privilege_tables.sql:
  Add new column 'time_zone' to mysql.event.
sql/event_data_objects.cc:
  The essence of the change is the following:
   - for internal times use my_time_t instead of TIME.  Assignment and
     comparison is done now on plain numbers.
   - in init_execute_at(), init_starts(), init_ends() convert given time
     to number of seconds since Epoch (aka Unix time, in UTC).
   - handle time_zone field loading and storing.
   - in get_next_time(), Unix time is converted back to event time zone,
     interval is added, and the result is converted to UTC again.
   - fix Event_timed::get_create_event() to report STARTS and ENDS.
   - before executing the event body we set thread time zone to the
     event time zone.
sql/event_data_objects.h:
  Add time_zone member to Event_basic class.
  
  Store internal times in my_time_t (number of seconds since Epoch),
  rather than in broken down TIME structure.
sql/event_db_repository.cc:
  Add time_zone column handling.
  
  Give a warning and do not create an event if its execution time is in
  the past, and ON COMPLETION NOT PRESERVE is set, because such an event
  should be dropped by that time.  Also, do not allow ALTER EVENT to
  set execution time in the past when ON COMPLETION NOT PRESERVE is set.
sql/event_db_repository.h:
  Add enum member for new time zone column.
sql/event_queue.cc:
  Replace handling of broken down times with simple handling of
  my_time_t.
sql/event_queue.h:
  Store internal times in my_time_t (number of seconds since Epoch),
  rather than in broken down TIME structure.
sql/event_scheduler.cc:
  Add TODO comment.
sql/events.cc:
  Send time_zone column for SHOW CREATE EVENT.
sql/share/errmsg.txt:
  Update error message, and add two more errors.
sql/sql_show.cc:
  Add TIME_ZONE column to the output of SHOW EVENTS.
mysql-test/r/events_time_zone.result:
  BitKeeper file /home/tomash/src/mysql_ab/mysql-5.1-wl3698/mysql-test/r/events_time_zone.result
mysql-test/t/events_time_zone.test:
  BitKeeper file /home/tomash/src/mysql_ab/mysql-5.1-wl3698/mysql-test/t/events_time_zone.test
2007-03-16 17:31:07 +03:00

102 lines
2.8 KiB
C++

#ifndef _EVENT_DB_REPOSITORY_H_
#define _EVENT_DB_REPOSITORY_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 */
#define EVEX_OPEN_TABLE_FAILED -1
enum enum_events_table_field
{
ET_FIELD_DB = 0,
ET_FIELD_NAME,
ET_FIELD_BODY,
ET_FIELD_DEFINER,
ET_FIELD_EXECUTE_AT,
ET_FIELD_INTERVAL_EXPR,
ET_FIELD_TRANSIENT_INTERVAL,
ET_FIELD_CREATED,
ET_FIELD_MODIFIED,
ET_FIELD_LAST_EXECUTED,
ET_FIELD_STARTS,
ET_FIELD_ENDS,
ET_FIELD_STATUS,
ET_FIELD_ON_COMPLETION,
ET_FIELD_SQL_MODE,
ET_FIELD_COMMENT,
ET_FIELD_TIME_ZONE,
ET_FIELD_COUNT /* a cool trick to count the number of fields :) */
};
int
events_table_index_read_for_db(THD *thd, TABLE *schema_table,
TABLE *event_table);
int
events_table_scan_all(THD *thd, TABLE *schema_table, TABLE *event_table);
class Event_basic;
class Event_parse_data;
class Event_db_repository
{
public:
Event_db_repository(){}
bool
create_event(THD *thd, Event_parse_data *parse_data, my_bool create_if_not);
bool
update_event(THD *thd, Event_parse_data *parse_data, LEX_STRING *new_dbname,
LEX_STRING *new_name);
bool
drop_event(THD *thd, LEX_STRING db, LEX_STRING name, bool drop_if_exists);
void
drop_schema_events(THD *thd, LEX_STRING schema);
bool
find_named_event(THD *thd, LEX_STRING db, LEX_STRING name, TABLE *table);
bool
load_named_event(THD *thd, LEX_STRING dbname, LEX_STRING name, Event_basic *et);
int
open_event_table(THD *thd, enum thr_lock_type lock_type, TABLE **table);
int
fill_schema_events(THD *thd, TABLE_LIST *tables, const char *db);
private:
void
drop_events_by_field(THD *thd, enum enum_events_table_field field,
LEX_STRING field_value);
bool
index_read_for_db_for_i_s(THD *thd, TABLE *schema_table, TABLE *event_table,
const char *db);
bool
table_scan_all_for_i_s(THD *thd, TABLE *schema_table, TABLE *event_table);
static bool
check_system_tables(THD *thd);
/* Prevent use of these */
Event_db_repository(const Event_db_repository &);
void operator=(Event_db_repository &);
};
#endif /* _EVENT_DB_REPOSITORY_H_ */