group_concat_max_len 最大默认1024,超过此长度不会报错会被截取
加大
SET GLOBAL group_concat_max_len = 10240000;
分类目录归档:MySQL
MySQL自动备份到亚马逊S3
#!/bin/sh
# Updates etc at: https://github.com/woxxy/MySQL-backup-to-Amazon-S3
# Under a MIT license
# change these variables to what you need
MYSQLROOT=XXX
MYSQLPASS=XXXX
S3BUCKET=xx-mysql-backup
# DATABASE='--all-databases'
DATABASE=${1-default}
FILENAME=${DATABASE}
HOST=master
DUMPOPTION='--quick --single-transaction'
# the following line prefixes the backups with the defined directory. it must be blank or end with a /
S3PATH=mysql-backup/${DATABASE}
# when running via cron, the PATHs MIGHT be different. If you have a custom/manual MYSQL install, you should set this manually like MYSQLDUMPPATH=/usr/local/mysql/bin/
MYSQLDUMPPATH=
#tmp path.
TMP_PATH=/tmp/
DATESTAMP=$(date +".%Y-%m-%d.%H:%M:%S")
DELDATESTAMP=$(date -d"15 day ago 2017-04-16" +".%Y-%m-%d.%H:%M:%S")
DAY=$(date +"%d")
DAYOFWEEK=$(date +"%A")
PERIOD=${2-day}
if [ ${PERIOD} = "auto" ]; then
if [ ${DAY} = "01" ]; then
PERIOD=month
elif [ ${DAYOFWEEK} = "Sunday" ]; then
PERIOD=week
else
PERIOD=day
fi
fi
echo "Selected period: $PERIOD."
echo "Starting backing up the database to a .gz file..."
# dump all databases
${MYSQLDUMPPATH}mysqldump -h${HOST} ${DUMPOPTION} --user=${MYSQLROOT} --password=${MYSQLPASS} ${DATABASE} | gzip > ${TMP_PATH}${FILENAME}.gz
echo "Done backing up the database to a file."
# echo "Starting compression..."
# tar czf ${TMP_PATH}${FILENAME}${DATESTAMP}.tar.gz ${TMP_PATH}${FILENAME}.sql
mv ${TMP_PATH}${FILENAME}.gz ${TMP_PATH}${FILENAME}${DATESTAMP}.gz
# echo "Done compressing the backup file."
# upload all databases
echo "Uploading the new backup..."
s3cmd put -f --check-md5 -s --continue-put ${TMP_PATH}${FILENAME}${DATESTAMP}.gz s3://${S3BUCKET}/${S3PATH}${PERIOD}/
echo "New backup uploaded."
if [ $? -ne 0 ]
then
echo "Re uploading the backup file..."
s3cmd put -f --check-md5 -s --continue-put ${TMP_PATH}${FILENAME}${DATESTAMP}.gz s3://${S3BUCKET}/${S3PATH}${PERIOD}/
echo "Re upload backup file done."
fi
echo "Moving the backup from past $PERIOD to another folder..."
s3cmd mv --recursive s3://${S3BUCKET}/${S3PATH}${PERIOD}/${FILENAME}${DELDATESTAMP} s3://${S3BUCKET}/${S3PATH}previous_${PERIOD}/
echo "Past backup moved."
# we want at least two backups, two months, two weeks, and two days
echo "Removing old backup (15 ${PERIOD}s ago)..."
s3cmd del --recursive s3://${S3BUCKET}/${S3PATH}previous_${PERIOD}/
echo "Old backup removed."
# remove databases dump
# rm ${TMP_PATH}${FILENAME}.sql
echo "Removing the gz files..."
rm ${TMP_PATH}${FILENAME}${DATESTAMP}.gz
echo "Files removed."
echo "All done."
Mariadb 修改数据目录,并且打开了SELinux,SELinux配置命令
Job for mariadb.service failed because the control process exited with error code. See “systemctl status mariadb.service” and “journalctl -xe” for details.
MySQL 8.0启动报错,也是这个问题(已经chown了)
mysqld: File ‘./binlog.index’ not found (OS errno 13 – Permission denied)
chcon -R -t mysqld_db_t /mnt/mysql
参考页面:https://www.thegeekstuff.com/2016/05/move-mysql-directory/
MySQL GET_LOCK函数实现MySQL加锁
GET_LOCK(str,timeout)
Tries to obtain a lock with a name given by the string str, using a timeout of timeout seconds. A negative timeout value means infinite timeout. The lock is exclusive. While held by one session, other sessions cannot obtain a lock of the same name.
- 尝试使用超时秒数的超时获得一个由字符串str给出的名称的锁。
- 负超时值意味着无限超时。
- 锁是独占的。
- 只能由一个会话持有,其他会话无法获得同名的锁。
参考:https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
参考:https://blog.csdn.net/tangtong1/article/details/51792617
MySQL二进制日志清理
- 查看过期天数
show variables like ‘%logs%’;
2. 设置过期天数(最大值为99)
set global expire_logs_days = 99;
MySQL8.0 支持binlog_expire_logs_seconds参数,顾名思义就是日志过期秒数。
自动二进制日志文件删除的天数。 默认值为0,表示“不自动删除”。 可能的删除发生在启动时和二进制日志刷新。
2.1 生效问题
flush logs;
如果你发现设置没有生效,可能需要执行此命令。
3. 查看现有的日志文件
SHOW BINARY LOGS;
4. 手动清理较旧日志
PURGE BINARY LOGS TO ‘mysql-bin.000007’;
将mysql-bin.000007以前的日志清理掉,又或者
PURGE BINARY LOGS BEFORE ‘2018-01-06 12:12:12’;
将2018-01-06 12:12:12以前的日志清理掉
5. 修改MySQL配置文件
expire_logs_days = 99
create table和主从复制一坑
正确:
CREATE TABLE `chapter_lock_reason` (
`id` INT(11) NOT NULL AUTO_INCREMENT
PRIMARY KEY (`id`)
);
错误的方式:
CREATE TABLE xxx.`chapter_lock_reason` (
`id` INT(11) NOT NULL AUTO_INCREMENT
PRIMARY KEY (`id`)
);
MySQL ARCHIVE 引擎,从库突然Can’t write; duplicate key in table ‘nopay_record” on query.
这是ARCHIVE引擎的BUG
Error ‘Can’t write; duplicate key in table ‘nopay_record” on query. Default database: ‘doufu’. Query: ‘insert into `nopay_record` (`user_id`, `novel_id`, `chapter_id`, `channel`, `created_at`) values (3927416, 365027, 2499984, NULL, ‘2017-12-29 23:38:01′)’
表结构:
CREATE TABLE `nopay_record` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`user_id` int(11) NOT NULL,
`novel_id` int(11) NOT NULL,
`chapter_id` int(11) NOT NULL,
`channel` tinyint(4) DEFAULT NULL,
`created_at` timestamp NOT NULL DEFAULT ‘0000-00-00 00:00:00’,
`updated_at` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`)
) ENGINE=ARCHIVE AUTO_INCREMENT=440357 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;
改成innodb吧
–slave-skip-errors 不支持下列值
1007,1008,1050,1051,1054,1060,1061,1068,1094,1146.
pt-duplicate-key-checker 检查重复的索引
pt-duplicate-key-checker --user=root --password=123456 --host=master D=dbname
–user 用户名
–password 密码
–host 数据库地址
D=dbname 检查dbname这数据库