启动MySQL5.7时报错:initialize specified but the data directory has files in it. Aborting.

启动MySQL5.7时报错：initialize specified but the data directory has files in it. Aborting

解决方法：

vim /etc/my.cnf
查看文件，寻找datadir=...
查看到：datadir=/usr/local/mysql/data,
这个是data保存目录。
进入/usr/local/mysql/data后，查看到确实有数据：
将/usr/local/mysql/data备份，
cd /usr/local/mysql
mv data data.bak
接着执行：
# mysqld --initialize-insecure --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data
# systemctl start mysqld