一个错误的示范 修改之后: 1NF(FIRST NORMAL FORM) 1NF的另一个表述是:若一个表中不包含任何重复的数据项,称这样的设计属于或服从第一范式。 每一Cell必须只有一个值。 不要把不同类型的数据插入同一列。 列名不要重复 2NF ...猜你喜欢还在为理解关系数据库的三范式而困惑,这篇文章用实例场景带你快速了解...
BCNF is considered to be the stronger than 3NF. The relation R to be in BCNF must be in3NF. And wherever anon-trivial functional dependency A -> Bholds in relation R, thenAmust be asuperkeyof relation R. As we know, Super key is a key which has a single attribute or set of attr...