如下，为什么这样写会报错，我是在MYSQL的控制台下写的？

Question

alter table name add column fieldname varchar(10) foreign key references table(filedname) on delete cascade;

Answer 1

alter table name add fieldname varchar(10) foreign key references table(filedname) on delete cascade;这样行么？如果不行的话， 就拆2条语句吧alter table name add fieldname varchar(10) ;alter table name ADD CONSTRAINT fk_name FOREIGN KEY (fieldname ) REFERENCES table(filedname) ON UPDATE CASCADE;