5.11.3. The General Query Log
The general query log is a general record of what
mysqld is doing. The server writes
information to this log when clients connect or disconnect, and
it logs each SQL statement received from clients. The general
query log can be very useful when you suspect an error in a
client and want to know exactly what the client sent to
mysqld.
mysqld writes statements to the query log in
the order that it receives them. This may be different from the
order in which they are executed. This is in contrast to the the
binary log, for which statements are written after they are
executed, but before any locks are released. (Also, the query
log contains all statements, whereas the binary log does not
contain statements that only select data.)
To enable the general query log as of MySQL 5.1.6, start
mysqld with the --log
option, and optionally use --log-output to
specify the log output destination as described in
Section 5.11.1, “Server Log Tables”. Before 5.1.6, enable the general
query log file with the
--log[=file_name] or
-l [file_name]
option. If no file_name value is
given, the default name is
host_name.log
Server restarts and log flushing do not cause a new general
query log file to be generated (although flushing closes and
reopens it). On Unix, you can rename the file and create a new
one by using the following commands:
shell> mv host_name.log host_name-old.log
shell> mysqladmin flush-logs
shell> cp host_name-old.log backup-directory
shell> rm host_name-old.log
On Windows, you cannot rename the log file while the server has
it open. You must stop the server and rename the file, and then
restart the server to create a new log file.
