Spec-Zone .ru
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Metadata about events can be obtained as follows:
Query the event
table of the mysql
database.
Query the EVENTS
table of the INFORMATION_SCHEMA
database. See Section 20.7, "The INFORMATION_SCHEMA EVENTS
Table".
Use the SHOW
CREATE EVENT
statement. See Section 13.7.5.9, "SHOW CREATE EVENT
Syntax".
Use the SHOW
EVENTS
statement. See Section 13.7.5.19, "SHOW EVENTS
Syntax".
Event Scheduler Time Representation
Each session in MySQL has a session time zone (STZ). This is the session time_zone
value that is initialized from the server's global time_zone
value when the session begins but may be changed during the session.
The session time zone that is current when a CREATE
EVENT
or ALTER EVENT
statement executes is used to interpret times specified in the event
definition. This becomes the event time zone (ETZ); that is, the time zone that is used for event scheduling and
is in effect within the event as it executes.
For representation of event information in the mysql.event
table, the execute_at
, starts
, and ends
times are converted to UTC and stored along with the event time zone. This
enables event execution to proceed as defined regardless of any subsequent changes to the server time zone or
daylight saving time effects. The last_executed
time is also stored in UTC.
If you select information from mysql.event
, the times just mentioned are retrieved
as UTC values. These times can also be obtained by selecting from the INFORMATION_SCHEMA.EVENTS
table or from SHOW EVENTS
, but they are reported as ETZ values. Other times available from
these sources indicate when an event was created or last altered; these are displayed as STZ values. The
following table summarizes representation of event times.
Value | mysql.event |
INFORMATION_SCHEMA.EVENTS
|
SHOW EVENTS
|
---|---|---|---|
Execute at | UTC | ETZ | ETZ |
Starts | UTC | ETZ | ETZ |
Ends | UTC | ETZ | ETZ |
Last executed | UTC | ETZ | n/a |
Created | STZ | STZ | n/a |
Last altered | STZ | STZ | n/a |