review what i studied `date` - 2017-4-27

USE Information_schema;
SELECT TABLE_NAME FROM COLUMNS WHERE COLUMN_NAME='字段名称';

ERROR 1701 (42000): Cannot truncate a table referenced in a foreign key
constraint (`furion`.`tbl_frn_alert`, CONSTRAINT `FK353A3CBEB139CC08`
FOREIGN KEY (`endpt_id`) REFERENCES `furion`.`tbl_frn_endpt` (`id`))
#解决方法：

mysql> SET foreign_key_checks=0;

#删除后

mysql> SET foreign_key_checks=1;

CREATE TABLE users_backup SELECT * FROM users;
#创建一个 users 表的备份表

truncate table 表名;
#清空一张表