前言

在最近的项目中，由于需要使用MySQL的UDF(user defined function)，这个特性从未使用过，而且个人觉得这个特性以后应该会经常使用，所以写下博文，记录和分享这个特性的用法。

UDF是mysql的一个拓展接口，UDF(Userdefined function)可翻译为用户自定义函数，这个是用来拓展Mysql的技术手段。

官方介绍请点击

有关MySQL5.7在CentOS7.0上的安装配置请参考

1. 下载

https://github.com/mysqludf/lib_mysqludf_sys

2. 安装

#安装mysql的两个依赖包

[root@dtadmin apollo ~]# rpm -ivh mysql-community-libs-compat-5.7.17-1.el7.x86_64.rpm

[root@dtadmin apollo ~]# rpm -ivh mysql-community-devel-5.7.17-1.el7.x86_64.rpm

#安装gcc gcc-c++编译器

[root@dtadmin apollo ~]# yum install gcc gcc-c++

3. 解压

[root@dtadmin apollo ~]# unzip lib_mysqludf_sys-master.zip

5. 执行命令

#进入目录

[root@dtadmin apollo ~]# cd lib_mysqludf_sys-master

# 在目录lib_mysqludf_sys-master执行：

[root@dtadmin lib_mysqludf_sys-master ~]# gcc -DMYSQL_DYNAMIC_PLUGIN -fPIC -Wall -I/usr/include/mysql -I. -shared lib_mysqludf_sys.c -o lib_mysqludf_sys.so

4. 把编译后的 lib_mysqludf_sys.so 拷到 /usr/lib64/mysql/plugin/

[root@dtadmin lib_mysqludf_sys-master ~]# cp lib_mysqludf_sys.so /usr/lib64/mysql/plugin/

6. 在mysql中执行

[root@dtadmin lib_mysqludf_sys-master ~]# mysql -u root -p --default-character-set=utf8

执行以下脚本：

Drop FUNCTION IF EXISTS lib_mysqludf_sys_info;

Drop FUNCTION IF EXISTS sys_get;

Drop FUNCTION IF EXISTS sys_set;

Drop FUNCTION IF EXISTS sys_exec;

Drop FUNCTION IF EXISTS sys_eval;

Create FUNCTION lib_mysqludf_sys_info RETURNS string SONAME 'lib_mysqludf_sys.so';

Create FUNCTION sys_get RETURNS string SONAME 'lib_mysqludf_sys.so';

Create FUNCTION sys_set RETURNS int SONAME 'lib_mysqludf_sys.so';

Create FUNCTION sys_exec RETURNS int SONAME 'lib_mysqludf_sys.so';

Create FUNCTION sys_eval RETURNS string SONAME 'lib_mysqludf_sys.so';

7.在/var/lib/mysql-files目录下新建脚本

[root@dtadmin lib_mysqludf_sys-master ~]# cd /var/lib/mysql-files

[root@dtadmin mysql-files ~]# load_data_infile.sh

脚本内容如下：

#!/bin/bash

HOSTNAME="192.168.56.101" #mysql hostname

PORT="3306" #mysql port

USERNAME="root" # the username for DBNAME

PASSWORD="Love88me=-.," # the password for USERNAME and DBNAME

DBNAME="subs" #DBNAME

cmd_load_data_infile="LOAD DATA INFILE '$1' REPLACE INTO TABLE $2 FIELDS TERMINATED BY '\t\t\t';"

mysql -h${HOSTNAME} -P${PORT} -u${USERNAME} -p${PASSWORD} -D${DBNAME} -e "${cmd_load_data_infile}"

8.改变文件的执行权限

[root@dtadmin mysql-files ~]# chmod u+x load_data_infile.sh

9.示例，定时备份数据表数据到另一张表

9.1.创建存储过程

use DBNAME;

drop table if exists sbux_nc_request_hist;

drop table if exists sbux_nc_edm_message_hist;

drop table if exists sbux_nc_mail_message_hist;

drop table if exists sbux_nc_push_message_hist;

drop table if exists sbux_nc_sms_message_hist;

drop table if exists sbux_nc_wechat_message_hist;

drop table if exists sbux_nc_sys_log_hist;

drop table if exists sbux_nc_sms_log_hist;

drop table if exists sbux_nc_push_log_hist;

drop table if exists sbux_nc_wechat_log_hist;

drop table if exists sbux_nc_edm_log_hist;

drop table if exists sbux_nc_mail_log_hist;

create table sbux_nc_request_hist like sbux_nc_request;

create table sbux_nc_edm_message_hist like sbux_nc_edm_message;

create table sbux_nc_mail_message_hist like sbux_nc_mail_message;

create table sbux_nc_push_message_hist like sbux_nc_push_message;

create table sbux_nc_sms_message_hist like sbux_nc_sms_message;

create table sbux_nc_wechat_message_hist like sbux_nc_wechat_message;

create table sbux_nc_sys_log_hist like sbux_nc_sys_log;

create table sbux_nc_edm_log_hist like sbux_nc_edm_log;

create table sbux_nc_mail_log_hist like sbux_nc_mail_log;

create table sbux_nc_push_log_hist like sbux_nc_push_log;

create table sbux_nc_sms_log_hist like sbux_nc_sms_log;

create table sbux_nc_wechat_log_hist like sbux_nc_wechat_log;

drop procedure if exists sbux_nc_data_migrate_p;

delimiter // ;

CREATE PROCEDURE sbux_nc_data_migrate_p()

BEGIN

DECLARE v_same_date_last_period date; # 上月同一天

DECLARE v_max_hist_date date; # 历史表中的最大时间

DECLARE v_current_date date; # 当前日期

DECLARE v_table_name varchar(50); # 变量，用来存储游标遍历中的要备份表的表名

DECLARE v_engine varchar(50); # 表的存储引擎

DECLARE v_create_options varchar(50); # 创建表的选项(是否是分区表)

DECLARE FLAG int default 0; # 游标的标记

DECLARE v_auto_increment int default 0; # 设置下个自增长列

DECLARE v_file_path varchar(200) default '/var/lib/mysql-files/'; # MySQL中的存储datafile的路径

DECLARE v_separator varchar(200) default " fields terminated by '\\t\\t\\t'"; # 导出文件的分隔符

DECLARE v_file varchar(500); # 导出文件的全名(路径+文件名)

DECLARE v_result int default 0; # 执行文件的结果标记

DECLARE v_flag int DEFAULT 0; # 执行shell脚本的标记

# 声明游标：查询出要做数据备份的表的列表

DECLARE cur_table_list CURSOR FOR

SELECT table_name, engine, create_options

FROM information_schema.TABLES

WHERE table_schema='DBMAME'

AND table_name in

(

'sbux_nc_request' ,

'sbux_nc_edm_message',

'sbux_nc_mail_message',

'sbux_nc_push_message',

'sbux_nc_sms_message',

'sbux_nc_wechat_message',

'sbux_nc_sys_log',

'sbux_nc_edm_log',

'sbux_nc_mail_log',

'sbux_nc_push_log',

'sbux_nc_sms_log',

'sbux_nc_wechat_log'

);

DECLARE CONTINUE HANDLER FOR NOT FOUND SET flag=1; #设置游标退出标记

SELECT date_sub(current_date(),interval 1 month) INTO v_same_date_last_period; # 查询上月同一天的日期

SELECT current_date() INTO v_current_date; # 查询当前日期

# 清空目录下面的文件

select sys_exec('rm -rf /var/lib/mysql-files/sbux_nc_*') into v_result;

# 遍历游标

OPEN cur_table_list;

FETCH cur_table_list INTO v_table_name,v_engine,v_create_options;

WHILE(flag<>1) DO

# 存储原表中所有数据到文件

SET @stmt = CONCAT('select * into outfile ',"'",v_file_path, v_table_name,'_hist.dat', "'",' ', v_separator, ' from ',v_table_name,';');

PREPARE stmt FROM @stmt;

EXECUTE stmt;

DEALLOCATE PREPARE stmt;

# 设置要备份表的时间段

SET @condition =

case v_table_name

when 'sbux_nc_request' then concat('where request_time between ',"'",v_same_date_last_period,"'", ' and ',"'", v_current_date,"'")

when 'sbux_nc_edm_message' then concat('where send_time between ',"'",v_same_date_last_period,"'", ' and ',"'", v_current_date,"'")

when 'sbux_nc_mail_message' then concat('where send_time between ',"'",v_same_date_last_period, "'",' and ',"'", v_current_date,"'")

when 'sbux_nc_push_message' then concat('where send_time between ',"'",v_same_date_last_period, "'",' and ',"'", v_current_date,"'")

when 'sbux_nc_sms_message' then concat('where send_time between ',"'",v_same_date_last_period, "'",' and ',"'", v_current_date,"'")

when 'sbux_nc_wechat_message' then concat('where send_time between ',"'",v_same_date_last_period, "'",' and ',"'", v_current_date,"'")

when 'sbux_nc_sys_log' then concat('where log_time between ',"'",v_same_date_last_period,"'", ' and ',"'", v_current_date,"'")

when 'sbux_nc_edm_log' then concat('where log_time between ',UNIX_TIMESTAMP(v_same_date_last_period), ' and ', UNIX_TIMESTAMP(v_current_date))

when 'sbux_nc_mail_log' then concat('where log_time between ',UNIX_TIMESTAMP(v_same_date_last_period), ' and ', UNIX_TIMESTAMP(v_current_date))

when 'sbux_nc_push_log' then concat('where log_time between ',UNIX_TIMESTAMP(v_same_date_last_period), ' and ', UNIX_TIMESTAMP(v_current_date))

when 'sbux_nc_sms_log' then concat('where log_time between ',UNIX_TIMESTAMP(v_same_date_last_period), ' and ', UNIX_TIMESTAMP(v_current_date))

when 'sbux_nc_wechat_log' then concat('where log_time between ',UNIX_TIMESTAMP(v_same_date_last_period), ' and ', UNIX_TIMESTAMP(v_current_date))

else NULL

end;

# 保存最近一个月的数据到文件

SET @stmt = CONCAT('select * into outfile ',"'", v_file_path, v_table_name,'.dat ', "'", ' ', v_separator, ' from ',v_table_name, ' ', @condition,';');

PREPARE stmt FROM @stmt;

EXECUTE stmt;

DEALLOCATE PREPARE stmt;

#获取表的最大增增长列并

select auto_increment into v_auto_increment

from information_schema.TABLES

where table_schema='starbucks'

and table_name=v_table_name;

# 删除原来数据

SET @stmt = CONCAT('truncate table ',v_table_name,';');

PREPARE stmt FROM @stmt;

EXECUTE stmt;

DEALLOCATE PREPARE stmt;

#设置下一个增量值

SET @stmt = CONCAT('alter table ',v_table_name,' auto_increment=',v_auto_increment,';');

PREPARE stmt FROM @stmt;

EXECUTE stmt;

DEALLOCATE PREPARE stmt;

# 加载数据到历史数据表中

# SET @stmt = CONCAT('LOAD DATA INFILE ',"'", v_file_path, v_table_name,'_hist.dat', "'", ' INTO TABLE ', v_table_name,'_hist',' ', v_separator);

# PREPARE stmt FROM @stmt;

# EXECUTE stmt;

# DEALLOCATE PREPARE stmt;

# 设置之前导出的表的数据文件(路径+文件名)

SET v_file = concat(v_file_path,v_table_name,'_hist.dat');

# 执行mysql UFF函数调用shell脚本把数据导入到历史表中

set @v_load_str = concat('sh /var/lib/mysql-files/load_data_infile.sh',' ',v_file,' ',CONCAT(v_table_name,'_hist'));

select sys_exec(@v_load_str) into v_flag;

# 把最近一个月的数据保存到原表中

# SET @stmt = CONCAT('LOAD DATA INFILE ',"'", v_file_path, v_table_name,'.dat ',"'",' INTO TABLE ',v_table_name,' ', v_separator);

# PREPARE stmt FROM @stmt;

# EXECUTE stmt;

# DEALLOCATE PREPARE stmt;

# 设置之前导出的表的近一个月数据文件(路径+文件名)

SET v_file = concat(v_file_path,v_table_name,'.dat');

# 执行mysql UFF函数调用shell脚本把数据导入到原表中

set @v_load_str = concat('sh /var/lib/mysql-files/load_data_infile.sh',' ',v_file,' ',v_table_name);

select sys_exec(@v_load_str) into v_flag;

# 收集(分析)表的数据

SET @stmt = CONCAT('analyze table ',v_table_name,';');

PREPARE stmt FROM @stmt;

EXECUTE stmt;

DEALLOCATE PREPARE stmt;

FETCH cur_table_list INTO v_table_name,v_engine,v_create_options;

END WHILE;

CLOSE cur_table_list;

END;

//

delimiter ; //

9.2.新建event,用来定时执行

/*======================================================================================== */

-- Name: sbux_nc_auto_migrate_evt

-- Purpose: 定时任务，自动备份表数据

-- Interval: Monthly

-- AT: 每个月1号凌晨2点

-- Invoker: sbux_nc_data_migrate_p

/*======================================================================================== */

set GLOBAL event_scheduler=1; # MySQL启动event scheduler

drop event if exists sbux_nc_auto_migrate_evt; # 在创建event scheduler前删除已存在的同名的event scheduler.

delimiter // ;

create event sbux_nc_auto_migrate_evt

ON SCHEDULE EVERY 1 DAY STARTS date_add(date(curdate() + 1),interval 2 hour) #MONTH STARTS DATE_ADD(DATE_ADD(DATE_SUB(CURDATE(),INTERVAL DAY(CURDATE())-1 DAY), INTERVAL 1 MONTH),INTERVAL 2 HOUR) -- 每个月的一号凌晨2点

ON completion preserve

ENABLE

DO

call sbux_nc_data_migrate_p();

//

delimiter ; //