mysql清除外键
清除所有外键：set foreign_key_checks=0;
逐个清除外键：alter table tbname drop foreign key foreign_key_name
?
SELECT
CONCAT(' ALTER TABLE ',TABLE_CONSTRAINTS.CONSTRAINT_SCHEMA,'.',TABLE_CONSTRAINTS.TABLE_NAME,'? DROP FOREIGN KEY? ',TABLE_CONSTRAINTS.CONSTRAINT_NAME,';')
FROM
TABLE_CONSTRAINTS WHERE CONSTRAINT_TYPE = 'FOREIGN KEY'
AND CONSTRAINT_SCHEMA IN ('ecshop')
?
MySQL官方文档 http://dev.mysql.com/doc/refman/5.1/zh/index.html
