是否任何行唯一标识是超级密钥 [英] Is it any row uniquely identify is superkey

问题描述

我怀疑超级密钥，任何字段组合都是唯一标识表中的每一行或任何行。 b b / b> b 。< br $>


必须是每一行唯一标识或任何行唯一标识是超级钥匙



我有什么尝试过：

我对超级密钥有疑问，任何字段组合都唯一标识
 
 表格中的每一行或任何一行。 
 
必须是每一行唯一标识或任何行唯一标识是超级键

解决方案

超级键是一个列表用于定义值的唯一组合的列。总有一个超级键，所有列，但是还可以有几个其他表的超级键。



看看Superkey - Wikipedia [ ^ ]

I have doubt on superkey that is any combination of fields is uniquely identify the

each row or any row in table.

must be each row uniquely identify or any row uniquely identify is superkey

What I have tried:

I have doubt on superkey that is any combination of fields is uniquely identify the 

each row or any row in table.

must be each row uniquely identify or any row uniquely identify is superkey

解决方案

Superkey is a list of columns that defines a unique combination for the values. There is always one superkey, all columns, but there can also be several other superkeys for a table.

Have a look at Superkey - Wikipedia[^]

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