一、MySQL简介
MySQL是一个关系型数据库管理系统,由瑞典MySQL AB 公司开发,目前属于 Oracle 旗下产品。MySQL 是最流行的关系型数据库管理系统之一,在 WEB 应用方面,MySQL是最好的 RDBMS (Relational Database Management System,关系数据库管理系统) 应用软件。
MySQL所使用的 SQL 语言是用于访问数据库的最常用标准化语言。MySQL 软件采用了双授权政策,分为社区版和商业版,由于其体积小、速度快、总体拥有成本低,尤其是开放源码这一特点,一般中小型网站的开发都选择 MySQL 作为网站数据库。
二、安装MySQL 5.7
MySQL 官网下载MySQL 5.7二进制包 https://www.mysql.com
(1)创建mysql用户和组
# groupadd mysql
# useradd -M -s /sbin/nologin -g mysql mysql
(2)解压软件包,将其做好链接,通常我们会把自己安装的软件包放在 /usr/local/ 目录下
# tar -zxf /usr/local/src/mysql-5.7.23-linux-glibc2.12-x86_64.tar.gz -C /usr/local/
# cd /usr/local
# ln -s mysql-5.7.23-linux-glibc2.12-x86_64/ mysql
(3)创建 mysql 的数据目录
# mkdir /usr/local/mysql/data
(4)将 mysql 的家目录以及数据目录都赋予 mysql用户组 和 mysql 用户的权限
# chown -R mysql:mysql /usr/local/mysql/
# chown -R mysql:mysql /usr/local/mysql/data/
(5)准备好 mysql 的配置文件 my.cnf
# The following options will be passed to all MySQL clients
[client]
#password = your_password
port = 3306
socket = /tmp/mysql.sock# The MySQL server
[mysqld]
basedir = /usr/local/mysql
datadir = /usr/local/mysql/data
port = 3306
socket = /tmp/mysql.sock
skip-external-locking
key_buffer_size = 16M
max_allowed_packet = 1M
table_open_cache = 64
sort_buffer_size = 512K
net_buffer_length = 8K
read_buffer_size = 256K
read_rnd_buffer_size = 512K
myisam_sort_buffer_size = 8M
#skip-networking
log-bin=mysql-binbinlog_format=mixed
server-id = 1
# Uncomment the following if you are using InnoDB tables
#innodb_data_home_dir = /usr/local/mysql/data
#innodb_data_file_path = ibdata1:10M:autoextend
#innodb_log_group_home_dir = /usr/local/mysql/data
# You can set .._buffer_pool_size up to 50 - 80 %
# of RAM but beware of setting memory usage too high
#innodb_buffer_pool_size = 16M
#innodb_additional_mem_pool_size = 2M
# Set .._log_file_size to 25 % of buffer pool size
#innodb_log_file_size = 5M
#innodb_log_buffer_size = 8M
#innodb_flush_log_at_trx_commit = 1
#innodb_lock_wait_timeout = 50[mysqldump]
quick
max_allowed_packet = 16M[mysql]
prompt="\u@\h \R:\m:\s[\d]> "
no-auto-rehash
# Remove the next comment character if you are not familiar with SQL
#safe-updates[myisamchk]
key_buffer_size = 20M
sort_buffer_size = 20M
read_buffer = 2M
write_buffer = 2M[mysqlhotcopy]
interactive-timeout
(6)准备好 mysql 的启动脚本文件,并存放为 /etc/init.d/mysqld,并赋予执行权限
#!/bin/sh
# Copyright Abandoned 1996 TCX DataKonsult AB & Monty Program KB & Detron HB
# This file is public domain and comes with NO WARRANTY of any kind# MySQL daemon start/stop script.
# Usually this is put in /etc/init.d (at least on machines SYSV R4 based
# systems) and linked to /etc/rc3.d/S99mysql and /etc/rc0.d/K01mysql.
# When this is done the mysql server will be started when the machine is
# started and shut down when the systems goes down.# Comments to support chkconfig on RedHat Linux
# chkconfig: 2345 64 36
# description: A very fast and reliable SQL database engine.# Comments to support LSB init script conventions
### BEGIN INIT INFO
# Provides: mysql
# Required-Start: $local_fs $network $remote_fs
# Should-Start: ypbind nscd ldap ntpd xntpd
# Required-Stop: $local_fs $network $remote_fs
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: start and stop MySQL
# Description: MySQL is a very fast and reliable SQL database engine.
### END INIT INFO
# If you install MySQL on some other places than /usr/local/mysql, then you
# have to do one of the following things for this script to work:
#
# - Run this script from within the MySQL installation directory
# - Create a /etc/my.cnf file with the following information:
# [mysqld]
# basedir=<path-to-mysql-installation-directory>
# - Add the above to any other configuration file (for example ~/.my.ini)
# and copy my_print_defaults to /usr/bin
# - Add the path to the mysql-installation-directory to the basedir variable
# below.
#
# If you want to affect other MySQL variables, you should make your changes
# in the /etc/my.cnf, ~/.my.cnf or other MySQL configuration files.# If you change base dir, you must also change datadir. These may get
# overwritten by settings in the MySQL configuration files.basedir=
datadir=# Default value, in seconds, afterwhich the script should timeout waiting
# for server start.
# Value here is overriden by value in my.cnf.
# 0 means don't wait at all
# Negative numbers mean to wait indefinitely
service_startup_timeout=900# Lock directory for RedHat / SuSE.
lockdir='/var/lock/subsys'
lock_file_path="$lockdir/mysql"# The following variables are only set for letting mysql.server find things.
# Set some defaults
mysqld_pid_file_path=
if test -z "$basedir"
then
basedir=/usr/local/mysql
bindir=/usr/local/mysql/bin
if test -z "$datadir"
then
datadir=/usr/local/mysql/data
fi
sbindir=/usr/local/mysql/bin
libexecdir=/usr/local/mysql/bin
else
bindir="$basedir/bin"
if test -z "$datadir"
then
datadir="$basedir/data"
fi
sbindir="$basedir/sbin"
libexecdir="$basedir/libexec"
fi# datadir_set is used to determine if datadir was set (and so should be
# *not* set inside of the --basedir= handler.)
datadir_set=#
# Use LSB init script functions for printing messages, if possible
#
lsb_functions="/lib/lsb/init-functions"
if test -f $lsb_functions ; then
. $lsb_functions
else
log_success_msg()
{
echo " SUCCESS! $@"
}
log_failure_msg()
{
echo " ERROR! $@"
}
fiPATH="/sbin:/usr/sbin:/bin:/usr/bin:$basedir/bin"
export PATHmode=$1 # start or stop
[ $# -ge 1 ] && shift
other_args="$*" # uncommon, but needed when called from an RPM upgrade action
# Expected: "--skip-networking --skip-grant-tables"
# They are not checked here, intentionally, as it is the resposibility
# of the "spec" file author to give correct arguments only.case `echo "testing\c"`,`echo -n testing` in
*c*,-n*) echo_n= echo_c= ;;
*c*,*) echo_n=-n echo_c= ;;
*) echo_n= echo_c='\c' ;;
esacparse_server_arguments() {
for arg do
case "$arg" in
--basedir=*) basedir=`echo "$arg" | sed -e 's/^[^=]*=//'`
bindir="$basedir/bin"
if test -z "$datadir_set"; then
datadir="$basedir/data"
fi
sbindir="$basedir/sbin"
libexecdir="$basedir/libexec"
;;
--datadir=*) datadir=`echo "$arg" | sed -e 's/^[^=]*=//'`
datadir_set=1
;;
--pid-file=*) mysqld_pid_file_path=`echo "$arg" | sed -e 's/^[^=]*=//'` ;;
--service-startup-timeout=*) service_startup_timeout=`echo "$arg" | sed -e 's/^[^=]*=//'` ;;
esac
done
}wait_for_pid () {
verb="$1" # created | removed
pid="$2" # process ID of the program operating on the pid-file
pid_file_path="$3" # path to the PID file.i=0
avoid_race_condition="by checking again"while test $i -ne $service_startup_timeout ; do
case "$verb" in
'created')
# wait for a PID-file to pop into existence.
test -s "$pid_file_path" && i='' && break
;;
'removed')
# wait for this PID-file to disappear
test ! -s "$pid_file_path" && i='' && break
;;
*)
echo "wait_for_pid () usage: wait_for_pid created|removed pid pid_file_path"
exit 1
;;
esac# if server isn't running, then pid-file will never be updated
if test -n "$pid"; then
if kill -0 "$pid" 2>/dev/null; then
: # the server still runs
else
# The server may have exited between the last pid-file check and now.
if test -n "$avoid_race_condition"; then
avoid_race_condition=""
continue # Check again.
fi# there's nothing that will affect the file.
log_failure_msg "The server quit without updating PID file ($pid_file_path)."
return 1 # not waiting any more.
fi
fiecho $echo_n ".$echo_c"
i=`expr $i + 1`
sleep 1done
if test -z "$i" ; then
log_success_msg
return 0
else
log_failure_msg
return 1
fi
}# Get arguments from the my.cnf file,
# the only group, which is read from now on is [mysqld]
if test -x ./bin/my_print_defaults
then
print_defaults="./bin/my_print_defaults"
elif test -x $bindir/my_print_defaults
then
print_defaults="$bindir/my_print_defaults"
elif test -x $bindir/mysql_print_defaults
then
print_defaults="$bindir/mysql_print_defaults"
else
# Try to find basedir in /etc/my.cnf
conf=/etc/my.cnf
print_defaults=
if test -r $conf
then
subpat='^[^=]*basedir[^=]*=\(.*\)$'
dirs=`sed -e "/$subpat/!d" -e 's//\1/' $conf`
for d in $dirs
do
d=`echo $d | sed -e 's/[ ]//g'`
if test -x "$d/bin/my_print_defaults"
then
print_defaults="$d/bin/my_print_defaults"
break
fi
if test -x "$d/bin/mysql_print_defaults"
then
print_defaults="$d/bin/mysql_print_defaults"
break
fi
done
fi# Hope it's in the PATH ... but I doubt it
test -z "$print_defaults" && print_defaults="my_print_defaults"
fi#
# Read defaults file from 'basedir'. If there is no defaults file there
# check if it's in the old (depricated) place (datadir) and read it from there
#extra_args=""
if test -r "$basedir/my.cnf"
then
extra_args="-e $basedir/my.cnf"
else
if test -r "$datadir/my.cnf"
then
extra_args="-e $datadir/my.cnf"
fi
fiparse_server_arguments `$print_defaults $extra_args mysqld server mysql_server mysql.server`
#
# Set pid file if not given
#
if test -z "$mysqld_pid_file_path"
then
mysqld_pid_file_path=$datadir/`hostname`.pid
else
case "$mysqld_pid_file_path" in
/* ) ;;
* ) mysqld_pid_file_path="$datadir/$mysqld_pid_file_path" ;;
esac
ficase "$mode" in
'start')
# Start daemon# Safeguard (relative paths, core dumps..)
cd $basedirecho $echo_n "Starting MySQL"
if test -x $bindir/mysqld_safe
then
# Give extra arguments to mysqld with the my.cnf file. This script
# may be overwritten at next upgrade.
$bindir/mysqld_safe --datadir="$datadir" --pid-file="$mysqld_pid_file_path" $other_args >/dev/null 2>&1 &
wait_for_pid created "$!" "$mysqld_pid_file_path"; return_value=$?# Make lock for RedHat / SuSE
if test -w "$lockdir"
then
touch "$lock_file_path"
fiexit $return_value
else
log_failure_msg "Couldn't find MySQL server ($bindir/mysqld_safe)"
fi
;;'stop')
# Stop daemon. We use a signal here to avoid having to know the
# root password.if test -s "$mysqld_pid_file_path"
then
mysqld_pid=`cat "$mysqld_pid_file_path"`if (kill -0 $mysqld_pid 2>/dev/null)
then
echo $echo_n "Shutting down MySQL"
kill $mysqld_pid
# mysqld should remove the pid file when it exits, so wait for it.
wait_for_pid removed "$mysqld_pid" "$mysqld_pid_file_path"; return_value=$?
else
log_failure_msg "MySQL server process #$mysqld_pid is not running!"
rm "$mysqld_pid_file_path"
fi# Delete lock for RedHat / SuSE
if test -f "$lock_file_path"
then
rm -f "$lock_file_path"
fi
exit $return_value
else
log_failure_msg "MySQL server PID file could not be found!"
fi
;;'restart')
# Stop the service and regardless of whether it was
# running or not, start it again.
if $0 stop $other_args; then
$0 start $other_args
else
log_failure_msg "Failed to stop running server, so refusing to try to start."
exit 1
fi
;;'reload'|'force-reload')
if test -s "$mysqld_pid_file_path" ; then
read mysqld_pid < "$mysqld_pid_file_path"
kill -HUP $mysqld_pid && log_success_msg "Reloading service MySQL"
touch "$mysqld_pid_file_path"
else
log_failure_msg "MySQL PID file could not be found!"
exit 1
fi
;;
'status')
# First, check to see if pid file exists
if test -s "$mysqld_pid_file_path" ; then
read mysqld_pid < "$mysqld_pid_file_path"
if kill -0 $mysqld_pid 2>/dev/null ; then
log_success_msg "MySQL running ($mysqld_pid)"
exit 0
else
log_failure_msg "MySQL is not running, but PID file exists"
exit 1
fi
else
# Try to find appropriate mysqld process
mysqld_pid=`pidof $libexecdir/mysqld`# test if multiple pids exist
pid_count=`echo $mysqld_pid | wc -w`
if test $pid_count -gt 1 ; then
log_failure_msg "Multiple MySQL running but PID file could not be found ($mysqld_pid)"
exit 5
elif test -z $mysqld_pid ; then
if test -f "$lock_file_path" ; then
log_failure_msg "MySQL is not running, but lock file ($lock_file_path) exists"
exit 2
fi
log_failure_msg "MySQL is not running"
exit 3
else
log_failure_msg "MySQL is running but PID file could not be found"
exit 4
fi
fi
;;
*)
# usage
basename=`basename "$0"`
echo "Usage: $basename {start|stop|restart|reload|force-reload|status} [ MySQL server options ]"
exit 1
;;
esacexit 0
# cp mysqld /etc/init.d/mysqld
# chmod +x /etc/init.d/mysqld
# chkconfig --add mysqld
# chkconfig mysqld on
(7)为方便使用 mysql 的相关命令,我们做好 $PATH 的环境变量
在文件的尾行,添加如下内容
# vim /etc/profile
export PATH=/usr/local/mysql/bin:$PATH
(8)获取临时密码 保存下来
# source /etc/profile
# mysqld --defaults-file=/etc/my.cnf --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data/ --user=mysql --initialize
2018-09-30T20:43:11.152551Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2018-09-30T20:43:11.154404Z 1 [Note] A temporary password is generated for root@localhost: ONyBguk1Wy<6
(9)启动 mysql 服务
# service mysqld start
(10)获取临时密码之后,用该密码登录 mysql
# mysql -uroot -p'ONyBguk1Wy<6'
三、修改密码
登录 mysql 之后修改 root 密码为123456
> alter user root@'localhost' identified by '123456';
Query OK, 0 rows affected (0.00 sec)
退出 mysql 终端 Ctrl + D
再次登录 mysql 无需再用临时密码 123456登录即可
# mysql -uroot -p123456