Databases Reference
In-Depth Information
variant of the MySQL server that includes some more cutting-edge (and less commonly
used) features. It also turns on server error logging, which you'd otherwise need to
specify as an option to
mysqld
, and automatically restarts the server if it crashes. Prior
to MySQL version 4, this was called
safe_mysqld
. On a Linux or OS X installation, you
will still find a symbolic link called
safe_mysqld
pointing to
mysqld_safe
.
MySQL Server Options
The MySQL server is a complex piece of software and has many settings that you can
tweak to make it better fit your needs. We'll discuss some of the more useful server
options here.
mysqld_safe
accepts a number of options of its own and passes on any
options it doesn't handle to
mysqld
. The options specific to
mysqld_safe
are probably
not of interest to most readers of this topic; you can find these by typing
mysqld_safe --help
at the command line:
basedir
This tells
mysqld
where MySQL is installed on the system. If you don't specify this
option, the program will try to use the location specified when the program was
compiled.
datadir
This tells
mysqld
where the database files are stored.
defaults-file
This specifies the location of the options file to read; this is particularly useful if
you want the server to read in options from a nondefault location.
enable-named-pipe
Allows a server running under Windows to use a named pipe. See
skip-networking
for more information.
init-file
This specifies a text file containing SQL commands that the server must execute
when starting up. This is commonly used to reset a forgotten MySQL root pass-
word as discussed in “Resetting Forgotten MySQL Passwords” in Chapter 9.
log
This tells
mysqld
to use the specified file to log every client connection and query.
log-bin
This specifies where you want the binary log of commands that attempt to modify
data on the server.
log-error
This tells
mysqld
to use the specified file to log server startup, shutdown, and errors.
By default, this is the file
<hostname>.err
in the data directory. For example, the
log might show that we've run out of disk space:
