mysql:functional dependency
2017-10-16 12:00 很大很老实 阅读(1763) 评论(1) 编辑 收藏 举报
First, a functional dependency in the form A->B means that, given one value for A, we can determine one and only one value for B. Both A and B represent sets of columns. (That's why they're written in uppercase letters.) |