MySQL in a Nutshell, 2nd Edition

Appendix C. Server and Environment Variables

The MySQL server and many of its clients and utilities use several environment variables provided by the operating system. For some programs, the user can override some of these variables by command-line options or values set in an options file (i.e., my.cnf or my.ini, depending on your system). Table C-1 lists the variables used.

Table C-1. Variables and their uses

Variable	Use
CC	C compiler
CXX	C++ compiler
CFLAGS	C compiler flags
CXXFLAGS	C++ compiler flags
DBI_USER	Default username for Perl DBI applications
DBI_TRACE	Perl DBI trace options
HOME	Default path for mysql client program history file
LD_RUN_PATH	Path for libmysqlclient.so file
MYSQL_DEBUG	Debug trace options
MYSQL_GROUP_SUFFIX	Relates to the value given with the --defaults-group-suffix option for a program like the mysql client
MYSQL_HISTFILE	Default path for the mysql client program history file
MYSQL_HOME	Contains the path for the server’s options file (e.g., my.cnf); available as of version 5.0.3 of MySQL
MYSQL_HOST	Default host for mysql client program
MYSQL_PS1	Command-line prompt for the first line of a statement for the mysql client program
MYSQL_PWD	Default password for connecting to the server
MYSQL_TCP_PORT	Default TCP/IP port number
MYSQL_UNIX_PORT	Default Unix socket filename
PATH	Path for the MySQL programs
TMPDIR	Path for a temporary directory
TZ	Timezone of the server
UMASK_DIR	Permissions settings for creating directories
UMASK	Permissions settings for creating files
USER	Default username for ...