内存溢出报错

2019-09-03T10:42:54.512893+08:00 0 [ERROR] InnoDB: Cannot allocate 1073742360 bytes of memory after 60 retries over 60 seconds. OS error: Cannot allocate memory (12). Check if you should increase the swap file or ulimits of your operating system. Note that on most 32-bit computers the process memory space is limited to 2 GB or 4 GB.

2019-09-03 10:42:54 0x7fbb69544780 InnoDB: Assertion failure in thread 140442902742912 in file ut0ut.cc line 957

解决办法:

修改配置my.conf文件内存大小，根据实际场景慢慢调优

innodb_buffer_pool_size =2048M

linux上是区分表名大小写的,但是可以通过 my.cnf文件中设置不区分！

MySQL8.0

2018-04-30T22:39:59.709423Z 1 [ERROR] [MY-011087] [Server] Different lower_case_table_names settings for server ('1') and data dictionary ('0').

解决修改配置文件

参数的含义及解决办法，vim /etc/my.cnf

lower_case_table_names： 此参数不可以动态修改，必须重启数据库

lower_case_table_names = 1 表名存储在磁盘是小写的，但是比较的时候是不区分大小写

lower_case_table_names=0 表名存储为给定的大小和比较是区分大小写的

lower_case_table_names=2, 表名存储为给定的大小写但是比较的时候是小写的

Linux安装MySQL5.7.29为摸个库授权

create user 用户名称@'%' identified by '密码';

GRANT ALL PRIVILEGES ON 库.* TO '用户'@'地址' IDENTIFIED BY 'dev' WITH GRANT OPTION;

grant all privileges on 库.* TO '用户'@'地址' identified by '密码';

MySQL OOM报错

解决办法：

https://cloud.tencent.com/developer/article/1478535

章页IO报错如下

解决办法修改：

vm.dirty_ratio <=20,vm.dirty_background_ratio <=10

MySQL权限问题

[root@mysql etc]# /usr/local/mysql/bin/mysqld --defaults-file=/etc/my.cnf --initialize 2019-04-18T10:54:00.803228+08:00 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details). 2019-04-18T10:54:00.807444+08:00 0 [ERROR] Could not open file '/data/mysql/mysql3306/logs/error.log' for error logging: Permission denied 2019-04-18T10:54:00.807484+08:00 0 [ERROR] Aborting

解决办法：请根据自己的环境授权目录

chown -R mysql.mysql /path/mysql

chown -R mysql.mysql /path/data/

常见MySQL初始化报错

/usr/local/mysql/bin/mysqld: error while loading shared libraries: libaio.so.1: cannot open shared object file: No such file or directory

解决办法：

yum -y install libaio

通过ldd命令查看so文件缺少

[root@mysql-5 mysql3306]# ldd /usr/local/mysql/bin/mysqld

linux-vdso.so.1 => (0x00007ffffc270000)

libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f8aac9d5000)

libaio.so.1 => /lib64/libaio.so.1 (0x00007f8aac7d3000)

libnuma.so.1 => /lib64/libnuma.so.1 (0x00007f8aac5c6000)

libcrypt.so.1 => /lib64/libcrypt.so.1 (0x00007f8aac38f000)

libdl.so.2 => /lib64/libdl.so.2 (0x00007f8aac18b000)

librt.so.1 => /lib64/librt.so.1 (0x00007f8aabf82000)

libstdc++.so.6 => /lib64/libstdc++.so.6 (0x00007f8aabc7a000)

libm.so.6 => /lib64/libm.so.6 (0x00007f8aab978000)

libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007f8aab761000)

libc.so.6 => /lib64/libc.so.6 (0x00007f8aab39e000)

/lib64/ld-linux-x86-64.so.2 (0x000056067c0fb000)

libfreebl3.so => /lib64/libfreebl3.so (0x00007f8aab19b000)

MySQL启动同时使用一个配置文件进程报错

2019-04-18T22:13:17.854048+08:00 0 [ERROR] InnoDB: Unable to lock ./ibdata1 error: 11

2019-04-18T22:13:17.854107+08:00 0 [Note] InnoDB: Check that you do not already have another mysqld process using the same InnoDB data or log files.

解决办法：

[root@mysql data]# cat mysql.pid

78783

查看当前MySQL当前的进程记录PID号，保留当前的PID号，杀掉最新的即可

解决办法：

[root@mysql data]# ps -ef|grep mysql

mysql 78783 1 0 19:08 ? 00:00:11 /usr/local/mysql/bin/mysqld

mysql 125815 94476 0 22:27 pts/0 00:00:00 /usr/local/mysql/bin/mysqld --defaults-file=/etc/my.cnf

利用ps -fe|grep mysql查看当前MySQL最新的进程PID号kill -9 PID号杀掉即可。

MySQL密码过期

[root@localhost mysql3306]# mysql -uroot -p -S /data/mysql3306/tmp/mysql.sock

Enter password:

ERROR 1862 (HY000): Your password has expired. To log in you must change it using a client that supports expired passwords.

解决办法：

my.cnf配置文件下添加skip-grant-tables跳过权限认证问题。

安全起见同时加入skip-networking关闭MySQL的TCP/IP连接方式。

[msyqld]

skip-grant-tables

skip-networking

说明：添加成功以后关闭MySQL重启MySQL不需要输入密码直接登陆

然后修改MySQL密码

update修改密码如下

mysql> use mysql #进入MySQL用户库

Database changed

mysql> show tables; # 查看当前库下的表

+---------------------------+

| Tables_in_mysql |

+---------------------------+

| columns_priv |

| user |

+---------------------------+

31 rows in set (0.00 sec)

查看表结构以下是MySQL5.7版本密码加密方式

mysql> desc user

| authentication_string | text | YES | | NULL

密码修改方式

update mysql.user setauthentication_string=password('新密码')where user='root';

flush privileges;

错误1820 (HY000):在执行此语句之前，必须使用ALTER USER语句重置密码。

ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.

解决办法：

alter user root@'localhost' identified by '新密码';

flush privileges;