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问题描述

我对数据库表中的唯一行有问题,现在可以这样做:

I have problem with unique rows in db table, now it is posible to do that:

id  | Name  | LastName  | City
-------------------------------------
1   | John  | Moore     | London
2   | John  | Moore     | London



when i use UNIQUE attribute in all columns i have errors inserting second Moore even it is different Name :/

如何使用UNIQUE(或INDEX?)在db中的表格中执行类似操作:

how use UNIQUE (or maybe INDEX?) to do something like that in my table in db:

id  | Name  | LastName  | City
-------------------------------------
1   | John  | Moore     | London
2   | Jake  | Moore     | London
3   | John  | Keen      | London
4   | John  | Moore     | London //but good error when inserting the same row

对不起,如果问题很容易,在sql,并有问题找到一些很好的例子使用UNIQUE像一个想:/
或者也许我必须在插入新行之前从数据库选择一个表,并检查是否存在?

Sorry if question is easy, but i am beginner at sql, and have problems with find some good example with using a UNIQUE like a want:/or maybe I must just before inserting a new row selecting a table from db and check if it exist?

推荐答案

删除单个列上的唯一索引,并将它们放在两个列上,如下所示:

Remove the unique index on the individual column and make it on both columns together, like this:

CREATE UNIQUE INDEX ixFullName ON yourTable (LastName, Name);

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10-24 16:07