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。
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.zip4. 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 5. 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/1
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.sh9.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 ; //