一：权限问题
前情提要：本来该数据库可以远程访问，后来我改了密码就发现不能远程访问，网上查找教程已经执行如下命令了，还包括重起mysql服务等等....
mysql>GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY '123456'; mysql> flush privileges;
mysql> select user, host from mysql.user;
+---------------+-----------+
| user | host |
+---------------+-----------+
| root | % |
| root | %% | -----------这是什么东东，看起来好怪，是哪一次我不小心加上去的么
| mysql.session | localhost |
| mysql.sys | localhost |
| root | localhost |
+---------------+-----------+
但是即是本地访问还是如下，远程访问(指定ip一样是这个错误)：
[root@wxy asm_1000]# mysql -h192.168.1.158 -uroot -p -NOK Enter password: ERROR 1045 (28000): Access denied for user 'root'@'wxy' (using password: YES) # mysql -hlocalhost -uroot -p123456 ---OK ... mysql>
解决：
mysql> delete from mysql.user where Host='%%';
mysql> flush privileges;
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二：添加字段(未完成)
1,如果不存在则添加，如果存在则更新某个字段
create table proxy_udp_connect (
uuid varchar(32) not null,
proxyuuid varchar(32) not null,
pctype int(1) not null comment '1 master, 2 slave',
protocoltype int(1) not null comment '1 2 tcp, 3 4 udp',
client_ip varchar(40) not null,
client_port int(5) not null,
bind_ip varchar(40) not null,
bind_port int(5) not null,
bind_fd int(5) not null,
connect_count int(5) not null,
primary key (uuid,client_ip,client_port)
);
insert into proxy_udp_connect(uuid,proxyuuid,pctype,protocoltype,client_ip,client_port,bind_ip,bind_port,bind_fd,connect_count) VALUES('1','123456',1,2,'192.168.1.158',1,'192.168.2.158',11,111,1) ON DUPLICATE KEY UPDATE connect_count=1+connect_count;
--------------------------------------------------------------
> create table test (
-> int5 int(5) not null,
-> int32 int(32) not null
-> );
Query OK, 0 rows affected (0.25 sec)
mysql> describe test;
+-------+---------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+---------+------+-----+---------+-------+
| int5 | int(5) | NO | | NULL | |
| int32 | int(32) | NO | | NULL | |
+-------+---------+------+-----+---------+-------+
2 rows in set (0.00 sec)
mysql> insert into test values(2147483647,2147483648);
ERROR 1264 (22003): Out of range value for column 'int32' at row 1
mysql> insert into test values(2147483647,2147483647);
Query OK, 1 row affected (0.02 sec)
mysql> select * from test;
+------------+------------+
| int5 | int32 |
+------------+------------+
| 12345 | 123456789 |
| 123456789 | 2147483647 |
| 2147483647 | 2147483647 |
+------------+------------+
3 rows in set (0.00 sec)
wxy：所以，int5和int32有什么区别么
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