MYSQLBINLOG(1)

NAME
mysqlbinlog - utility for processing binary log files

SYNOPSIS

mysqlbinlog [options] log-file ...

DESCRIPTION

The binary log files that the server generates are written in binary format. To examine these files in text format, use the mysqlbinlog utility.

Invoke mysqlbinlog like this:

shell> mysqlbinlog [options] log-file ...

For example, to display the contents of the binary log binlog.000003, use this command:

shell> mysqlbinlog binlog.0000003

The output includes all statements contained in binlog.000003, together with other information such as the time each statement took, the thread ID of the client that issued it, the timestamp when it was issued, and so forth.

Normally, you use mysqlbinlog to read binary log files directly and apply them to the local MySQL server. It is also possible to read binary logs from a remote server by using the --read-from-remote-server option.

When you read remote binary logs, the connection parameter options can be given to indicate how to connect to the server, but they are ignored unless you also specify the --read-from-remote-server option. These options are --host, --password, --port, --protocol, --socket, and --user.

You can also use mysqlbinlog to read relay log files written by a slave server in a replication setup. Relay logs have the same format as binary log files.

The binary log is discussed further in Section 8.3, “The Binary Log”.

mysqlbinlog supports the following options:

•   --help, -?

    Display a help message and exit.

•   --database=db_name, -d db_name

    List entries for just this database (local log only).

•   --force-read, -f

    With this option, if mysqlbinlog reads a binary log event that it does not recognize, it prints a warning, ignores the event, and continues. Without this option, mysqlbinlog stops if it reads such an event.

•   --hexdump, -H

    Display a hex dump of the log in comments. This output can be helpful for replication debugging. This option was added in MySQL 5.0.16.

•   --host=host_name, -h host_name

    Get the binary log from the MySQL server on the given host.

•   --local-load=path, -l path

    Prepare local temporary files for LOAD DATA INFILE in the specified directory.

•   --offset=N, -o N

    Skip the first N entries.

•   --password[=password], -p[password]

    The password to use when connecting to the server. If you use the short option form (-p), you cannot have a space between the option and the password. If you omit the password value following the --password or -p option on the command line, you are prompted for one.

•   --port=port_num, -P port_num

    The TCP/IP port number to use for connecting to a remote server.

•   --position=N, -j N

    Deprecated, use --start-position instead.

•   --protocol={TCP | SOCKET | PIPE | MEMORY}

    The connection protocol to use.

•   --read-from-remote-server, -R

    Read the binary log from a MySQL server. Any connection parameter options are ignored unless this option is given as well. These options are --host, --password, --port, --protocol, --socket, and --user.

•   --result-file=name, -r name

    Direct output to the given file.

•   --short-form, -s

    Display only the statements contained in the log, without any extra information.

•   --socket=path, -S path

    The socket file to use for the connection.

•   --start-datetime=datetime

    Start reading the binary log at the first event having a datetime equal to or later than the datetime argument. The datetime value is relative to the local time zone on the machine where you run mysqlbinlog. The value should be in a format accepted for the DATETIME or TIMESTAMP data types. For example:

    shell> mysqlbinlog --start-datetime="2004-12-25 11:25:56" binlog.000003
    This option is useful for point-in-time recovery.

•   --stop-datetime=datetime

    Stop reading the binary log at the first event having a datetime equal or posterior to the datetime argument. See the description of the --start-datetime option for information about the datetime value. It is useful for point-in-time recovery.

•   --start-position=N

    Start reading the binary log at the first event having a position equal to the N argument.

•   --stop-position=N

    Stop reading the binary log at the first event having a position equal or greater than the N argument.

•   --to-last-log, -t

    Do not stop at the end of the requested binary log of the MySQL server, but rather continue printing until the end of the last binary log. If you send the output to the same MySQL server, this may lead to an endless loop. This option requires --read-from-remote-server.

•   --disable-log-bin, -D

    Disable binary logging. This is useful for avoiding an endless loop if you use the --to-last-log option and are sending the output to the same MySQL server. This option also is useful when restoring after a crash to avoid duplication of the statements you have logged. Note: This option requires that you have the SUPER privilege.

•   --user=user_name, -u user_name

    The MySQL username to use when connecting to a remote server.

•   --version, -V

    Display version information and exit.

You can also set the following variable by using --var_name=value options:

•   open_files_limit

    Specify the number of open file descriptors to reserve.

You can pipe the output of mysqlbinlog into a mysql client to execute the statements contained in the binary log. This is used to recover from a crash when you have an old backup (see Section 6.1, “Database Backups”):

shell> mysqlbinlog hostname-bin.000001 | mysql

Or:

shell> mysqlbinlog hostname-bin.[0-9]* | mysql

You can also redirect the output of mysqlbinlog to a text file instead, if you need to modify the statement log first (for example, to remove statements that you do not want to execute for some reason). After editing the file, execute the statements that it contains by using it as input to the mysql program.

mysqlbinlog has the --position option, which prints only those statements with an offset in the binary log greater than or equal to a given position (the given position must match the start of one event). It also has options to stop or start when it sees an event of a given date and time. This enables you to perform point-in-time recovery using the --stop-datetime option (to be able to say, for example, “roll forward my databases to how they were today at 10:30 AM”).

If you have more than one binary log to execute on the MySQL server, the safe method is to process them all using a single connection to the server. Here is an example that demonstrates what may be unsafe:

shell> mysqlbinlog hostname-bin.000001 | mysql # DANGER!!
shell> mysqlbinlog hostname-bin.000002 | mysql # DANGER!!

Processing binary logs this way using different connections to the server causes problems if the first log file contains a CREATE TEMPORARY TABLE statement and the second log contains a statement that uses the temporary table. When the first mysql process terminates, the server drops the temporary table. When the second mysql process attempts to use the table, the server reports “unknown table”.

To avoid problems like this, use a single connection to execute the contents of all binary logs that you want to process. Here is one way to do this:

shell> mysqlbinlog hostname-bin.000001 hostname-bin.000002 | mysql

Another approach is to do this:

shell> mysqlbinlog hostname-bin.000001 >  /tmp/statements.sql
shell> mysqlbinlog hostname-bin.000002 >> /tmp/statements.sql
shell> mysql -e "source /tmp/statements.sql"

mysqlbinlog can produce output that reproduces a LOAD DATA INFILE operation without the original data file. mysqlbinlog copies the data to a temporary file and writes a LOAD DATA LOCAL INFILE statement that refers to the file. The default location of the directory where these files are written is system-specific. To specify a directory explicitly, use the --local-load option.

Because mysqlbinlog converts LOAD DATA INFILE statements to LOAD DATA LOCAL INFILE statements (that is, it adds LOCAL), both the client and the server that you use to process the statements must be configured to allow LOCAL capability. See Section 3.4, “Security Issues with LOAD DATA LOCAL”.

Warning: The temporary files created for LOAD DATA LOCAL statements are not automatically deleted because they are needed until you actually execute those statements. You should delete the temporary files yourself after you no longer need the statement log. The files can be found in the temporary file directory and have names like original_file_name-#-#.

The --hexdump option produces a hex dump of the log contents in comments:

shell> mysqlbinlog --hexdump master-bin.000001

With the preceding command, the output might look like this:

/*!40019 SET @@session.max_insert_delayed_threads=0*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
# at 4
#051024 17:24:13 server id 1  end_log_pos 98
# Position  Timestamp   Type   Master ID        Size      Master Pos    Flags
# 00000004 9d fc 5c 43   0f   01 00 00 00   5e 00 00 00   62 00 00 00   00 00
# 00000017 04 00 35 2e 30 2e 31 35  2d 64 65 62 75 67 2d 6c |..5.0.15.debug.l|
# 00000027 6f 67 00 00 00 00 00 00  00 00 00 00 00 00 00 00 |og..............|
# 00000037 00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00 |................|
# 00000047 00 00 00 00 9d fc 5c 43  13 38 0d 00 08 00 12 00 |.......C.8......|
# 00000057 04 04 04 04 12 00 00 4b  00 04 1a                |.......K...|
#       Start: binlog v 4, server v 5.0.15-debug-log created 051024 17:24:13
#       at startup
ROLLBACK;

The hex dump output contains the following elements:

•   Position: The byte position within the log file.

•   Timestamp: The event timestamp. In the example just shown, '9d fc 5c 43' is the representation of '051024 17:24:13' in hexadecimal.

•   Type: The type of the log event. '0f' means that the example event is a FORMAT_DESCRIPTION_EVENT. The types are:

    00  UNKNOWN_EVENT
        This event should never be present in the log.
    01  START_EVENT_V3
        This indicates the start of a log file written by MySQL 4 or earlier.
    02  QUERY_EVENT
        The most common type of events.  These contain queries executed
        on the master.
    03  STOP_EVENT
        Indicates that master has stopped.
    04  ROTATE_EVENT
        Written when the master switches to a new log file.
    05  INTVAR_EVENT
        Used mainly for AUTO_INCREMENT values and if the LAST_INSERT_ID()
        function is used in the statement.
    06  LOAD_EVENT
        Used for LOAD DATA INFILE in MySQL 3.23.
    07  SLAVE_EVENT
        Reserved for future use.
    08  CREATE_FILE_EVENT
        Used for LOAD DATA INFILE statements.  This indicates the start
        of execution of such a statement.  A temporary file is created
        on the slave.  Used in MySQL 4 only.
    09  APPEND_BLOCK_EVENT
        Contains data for use in a LOAD DATA INFILE statement.  The
        data is stored in the temporary file on the slave.
    0a  EXEC_LOAD_EVENT
        Used for LOAD DATA INFILE statements.  The contents of the
        temporary file is stored in the table on the slave.
        Used in MySQL 4 only.
    0b  DELETE_FILE_EVENT
        Rollback of LOAD DATA INFILE statement.  The temporary file
        should be deleted on slave.
    0c  NEW_LOAD_EVENT
        Used for LOAD DATA INFILE in MySQL 4 and earlier.
    0d  RAND_EVENT
        Used to send information about random values if the RAND()
        function is used in the query.
    0e  USER_VAR_EVENT
        Used to replicate user variables.
    0f  FORMAT_DESCRIPTION_EVENT
        This indicates the start of a log file written by MySQL 5 or later.
    10  XID_EVENT
        Event indicating commit of XA transaction
    11  BEGIN_LOAD_QUERY_EVENT
        Used for LOAD DATA statements in MySQL 5 and later.
    12  EXECUTE_LOAD_QUERY_EVENT
        Used for LOAD DATA statements in MySQL 5 and later.
    13  TABLE_MAP_EVENT
        Reserved for future use
    14  WRITE_ROWS_EVENT
        Reserved for future use
    15  UPDATE_ROWS_EVENT
        Reserved for future use
    16  DELETE_ROWS_EVENT
        Reserved for future use

•   Master ID: The server id of the master that created the event.

•   Size: The size in bytes of the event.

•   Master Pos: The position of the event in the original master log file.

•   Flags: 16 flags.

    01  LOG_EVENT_BINLOG_IN_USE_F
        Log file correctly closed (Used only in FORMAT_DESCRIPTION_EVENT)
        If this flag is set (if the flags are e.g. '01 00') in an
        FORMAT_DESCRIPTION_EVENT, then the log file has not been
        properly closed.  Most probably because of a master crash (for
        example, due to power failure).
    02  Reserved for future use.
    04  LOG_EVENT_THREAD_SPECIFIC_F
        Set if the event is dependent on the connection it was
        executed in (example '04 00'), e.g. if the event uses
        temporary tables.
    08  LOG_EVENT_SUPPRESS_USE_F
        Set in some circumstances when the event is not dependent on
        the current database
    The other flags are reserved for future use.

The hex dump output format might change in later releases.

SEE ALSO
msql2mysql(1), myisamchk(1), myisamlog(1), myisampack(1), mysql(1), mysql.server(1), mysql_config(1), mysql_fix_privilege_tables(1), mysql_zap(1), mysqlaccess(1), mysqladmin(1), mysqlcheck(1), mysqld(1), mysqld_multi(1), mysqld_safe(1), mysqldump(1), mysqlhotcopy(1), mysqlimport(1), mysqlmanager(1), mysqlshow(1), perror(1), replace(1), safe_mysqld(1)

For more information, please refer to the MySQL Reference Manual, which may already be installed locally and which is also available online at http://dev.mysql.com/doc/.

AUTHOR
MySQL AB (http://www.mysql.com/). This software comes with no warranty.