----- On May 20, 2016, at 8:38 PM, Bernd Lentes 
bernd.len...@helmholtz-muenchen.de wrote:

> Hi,
> 
> i'm currently creating a replication and got in contact with the binlog. I use
> row-based logging. I read already the doc but i still have some questions.
> Maybe you can help me.
> 
> An excerp from a relay-log:
> 
> # at 329
> #160520 17:00:01 server id 1  end_log_pos 259   Query   thread_id=94
> exec_time=3     error_code=0
> SET TIMESTAMP=1463756401/*!*/;
> SET @@session.sql_mode=524288/*!*/;
> /*!\C latin1 *//*!*/;
> SET
> @@session.character_set_client=8,@@session.collation_connection=8,@@session.collation_server=33/*!*/;
> BEGIN
> /*!*/;
> # at 405
> #160520 17:00:01 server id 1  end_log_pos 410   Query   thread_id=94
> exec_time=3     error_code=0
> use `percona`/*!*/;
> SET TIMESTAMP=1463756401/*!*/;
> DELETE FROM `percona`.`checksums` WHERE db = 'mausdb' AND tbl = 
> 'GTAS_line_info'
> /*!*/;
> # at 556
> #160520 17:00:01 server id 1  end_log_pos 437   Xid = 785606
> COMMIT/*!*/;
> # at 583
> #160520 17:00:04 server id 1  end_log_pos 512   Query   thread_id=94
> exec_time=0     error_code=0
> SET TIMESTAMP=1463756404/*!*/;
> 
> Let's begin with "at 329". Ok, that's the byte offset of the event. Next line:
> Why is here the end_log_pos 259 before the Byte-Offset one line above ? Same
> happen later on again.
> Exec_time is 3. Milliseconds, seconds ... ?
> SET TIMESTAMP=1463756401/*!*/; How can i interpret "1463756401" ? Is there a 
> way
> to calculate to get a sensefull timestamp ?
> Xid = 785606. What is Xid ? An id of the event ?
> 
> 
> 

I found out what Xid is:
The doc says:
"Xid_log_event/XID_EVENT

An XID event is generated for a commit of a transaction that modifies one or 
more tables of an XA-capable storage engine. Strictly speaking, Xid_log_event 
is used if thd->transaction.xid_state.xid.get_my_xid() returns nonzero.

Here is an example of how to generate an XID event (it occurs whether or not 
innodb_support_xa is enabled):

CREATE TABLE t1 (a INT) ENGINE = INNODB;
START TRANSACTION;
INSERT INTO t1 VALUES (1);
COMMIT;
Fixed data part:

Empty

Variable data part:

8 bytes. The XID transaction number.

Note: Contrary to all other numeric fields, the XID transaction number is not 
always written in little-endian format. The bytes are copied unmodified from 
memory to disk, so the format is machine-dependent. Hence, when replicating 
from a little-endian to a big-endian machine (or vice versa), the numeric value 
of transaction numbers will differ. In particular, the output of mysqlbinlog 
differs. This should does not cause inconsistencies in replication because the 
only important property of transaction numbers is that different transactions 
have different numbers (relative order does not matter).

Begin_load_query_log_event/BEGIN_LOAD_QUERY_EVENT

This event is used for LOAD DATA INFILE statements. See also LOAD DATA INFILE 
Events."

https://dev.mysql.com/doc/internals/en/event-data-for-specific-event-types.html


Bernd
 

Helmholtz Zentrum Muenchen
Deutsches Forschungszentrum fuer Gesundheit und Umwelt (GmbH)
Ingolstaedter Landstr. 1
85764 Neuherberg
www.helmholtz-muenchen.de
Aufsichtsratsvorsitzende: MinDir'in Baerbel Brumme-Bothe
Geschaeftsfuehrer: Prof. Dr. Guenther Wess, Dr. Alfons Enhsen, Renate Schlusen 
(komm.)
Registergericht: Amtsgericht Muenchen HRB 6466
USt-IdNr: DE 129521671


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