1.进入官网下载MySQL5.7的安装包。
下载地址：https://www.mysql.com/downloads/
跟着上面图示下载即可，我这里选择的是5.7.31的版本，根据个人喜好选择版本，但是注意有的版本是没有mac版本的，换个版本就行了。
2.安装包下载完成后双击pkg文件进行安装，无脑点下一步即可，注意安装完成后记得保存最后弹出框的密码，如下图所示：
红色框的内容就是需要保存的，这是你mysql root账号的密码。
3.进入系统设置，找到mysql，开启mysql服务，如图所示：
出现下面图示情况就是mysql服务开启成功
4.打开终端，输入“sudo vim /etc/my.cnf”，在弹出的编辑器中按键盘的 i键进入编辑模式，输入以下内容：
# Example MySQL config file for medium systems.
#
# This is for a system with little memory (32M - 64M) where MySQL plays
# an important part, or systems up to 128M where MySQL is used together with
# other programs (such as a web server)
#
# MySQL programs look for option files in a set of
# locations which depend on the deployment platform.
# You can copy this option file to one of those
# locations. For information about these locations, see:
# http://dev.mysql.com/doc/mysql/en/option-files.html
#
# In this file, you can use all long options that a program supports.
# If you want to know which options a program supports, run the program
# with the "--help" option.
# The following options will be passed to all MySQL clients
[client]
default-character-set=utf8
#password = your_password
port = 3306
socket = /tmp/mysql.sock
# Here follows entries for some specific programs
# The MySQL server
[mysqld]
character-set-server=utf8
init_connect='SET NAMES utf8
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
character-set-server=utf8
init_connect='SET NAMES utf8'
# Don't listen on a TCP/IP port at all. This can be a security enhancement,
# if all processes that need to connect to mysqld run on the same host.
# All interaction with mysqld must be made via Unix sockets or named pipes.
# Note that using this option without enabling named pipes on Windows
# (via the "enable-named-pipe" option) will render mysqld useless!
#
#skip-networking
# Replication Master Server (default)
# binary logging is required for replication
log-bin=mysql-bin
# binary logging format - mixed recommended
binlog_format=mixed
# required unique id between 1 and 2^32 - 1
# defaults to 1 if master-host is not set
# but will not function as a master if omitted
server-id = 1
# Replication Slave (comment out master section to use this)
#
# To configure this host as a replication slave, you can choose between
# two methods :
#
# 1) Use the CHANGE MASTER TO command (fully described in our manual) -
# the syntax is:
#
# CHANGE MASTER TO MASTER_HOST=, MASTER_PORT=,
# MASTER_USER=, MASTER_PASSWORD= ;
#
# where you replace , , by quoted strings and
# by the master's port number (3306 by default).
#
# Example:
#
# CHANGE MASTER TO MASTER_HOST='125.564.12.1', MASTER_PORT=3306,
# MASTER_USER='joe', MASTER_PASSWORD='secret';
#
# OR
#
# 2) Set the variables below. However, in case you choose this method, then
# start replication for the first time (even unsuccessfully, for example
# if you mistyped the password in master-password and the slave fails to
# connect), the slave will create a master.info file, and any later
# change in this file to the variables' values below will be ignored and
# overridden by the content of the master.info file, unless you shutdown
# the slave server, delete master.info and restart the slaver server.
# For that reason, you may want to leave the lines below untouched
# (commented) and instead use CHANGE MASTER TO (see above)
#
# required unique id between 2 and 2^32 - 1
# (and different from the master)
# defaults to 2 if master-host is set
# but will not function as a slave if omitted
#server-id = 2
#
# The replication master for this slave - required
#master-host =
#
# The username the slave will use for authentication when connecting
# to the master - required
#master-user =
#
# The password the slave will authenticate with when connecting to
# the master - required
#master-password =
#
# The port the master is listening on.
# optional - defaults to 3306
#master-port =
#
# binary logging - not required for slaves, but recommended
#log-bin=mysql-bin
# 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]
no-auto-rehash
# Remove the next comment character if you are not familiar with SQL
#safe-updates
default-character-set=utf8
[myisamchk]
key_buffer_size = 20M
sort_buffer_size = 20M
read_buffer = 2M
write_buffer = 2M
[mysqlhotcopy]
interactive-timeout
编辑完成后，点击esc，然后将输入法设置为英文模式，输入:wq回车保存(注意wq前面的冒号也需要输入)。
5.设置文件权限
打开终端，输入“sudo chmod 664 /etc/my.cnf”，在系统设置中重启mysql服务，到此mysql安装大功告成。
注：我也不清楚第四步和第五步是在干什么，个人也是网上借鉴的别人的做法，多做这两步也不吃亏。
6.配置mysql环境变量。
打开终端，输入“open -e .bash_profile”回车，在弹出的文本编辑框内加入下面的代码，保存退出。
PATH=$PATH:/usr/local/mysql-5.7.31-macos10.14-x86_64/bin
7.在终端使用“source .bash_profile”命令，使配置生效。
8.在终端中使用“mysql -uroot -p”命令，然后提示要求输入密码(输入时密码不可见，不要以为没有输入上，把上面记录下来的密码复制粘贴直接回车即可)。
进入mysql后可以依次使用下面的命令修改密码（红色部分为需要修改的密码，根据个人喜好修改）：
SET PASSWORD FOR 'root'@'localhost' = PASSWORD('yourpassword');
FLUSH PRIVILEGES;
到此为止所有配置都完成，可以使用Navicat等第三方工具连接Mysql进行使用了。
最后注意：如果终端关闭重新打开，是不可以直接使用“mysql -uroot -p”命令进入mysql的，需要在此之前使用一次“source .bash_profile”命令，所以mysql环境配好后，建议使用第三方工具进行数据库相关操作。