1. mysql 的 smallint 区域是0-32767 之间
2. 打开日志
show variables like 'log_bin'; OFF 》》 NO
# [mysqld] 下面加入
log-bin=mysql-bin
binlog-format=MIXED
3.rpm -qa|grep -i mysql查看mysql
4.Starting MySQL...The server quit without updating PID file [失败]lib/mysql/localhost.localdomain.pid).
1).character-set_server=utf8
2).日志过大导致启动失败
5.mysql -h 127.0.0.1 -u dh -p
其他机器登录不了
错误ACCESS localhost
GRANT ALL PRIVILEGES ON root.* TO 'root'@'%' WITH GRANT OPTION;
没有权限登录
mysql> GRANT ALL PRIVILEGES ON root.* TO 'root'@'%' WITH GRANT OPTION;
ERROR 1133 (42000): Can't find any matching row in the user table
解决:GRANT ALL PRIVILEGES ON root.* TO 'root'@'%' identified by '123456' WITH GRANT OPTION
单库数据库-->数据库读写分离-->缓存技术-->搜索技术-->数据的垂直拆分(多库多表)-->数据的水平拆分(单表多库)