執行下面的SQL語句創建表失敗，請問各位該如何解決？謝謝!!
CREATE table enrolls
(sno numeric(6,0) not null,
cno char(4) not null,
grade int
primary key (sno,cno)
foreign key (sno) references students(sno)
foreign key (cno) references courses(cno)
check((grade is null)or(grade between 0 and 100)))
錯誤提示：More than one column FOREIGN KEY constraint specified for column 'grade ', table 'enrolls '.
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CREATE table enrolls
(sno numeric(6,0) not null,
cno char(4) not null,
grade int ,
primary key (sno,cno),
foreign key (sno) references students(sno),
foreign key (cno) references courses(cno),
check((grade is null)or(grade between 0 and 100)))
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...豆号
------解决方案--------------------
‘，’逗号，不加的话，就把后面的约束全当成是grade字段的了，自然就more than...了