现有表上带有nu唯一字段的SQL主键 [英] SQL Primary Key Required on existing table with nu unique field

问题描述

我有一个SQL表，上面有大量数据.没有主键，并且表上没有唯一字段.

我复制了结构和一些数据，并能够通过设计添加主键字段，但是当我在原始表上尝试相同时，它会超时.

我知道的唯一另一种方法是添加一列，手动填充字段，然后设置键，但是有超过一百万条记录.

请问还有另一种方法吗?

Hi,

I have a SQL table with a large quantity of data on it. There is no primary key and there is no unique field on the table.

I copied the structure and some data and was able to add a primary key field through design, but when I try the same on the original table it times out.

The only other way I know would be to add a column, populate the field manually and then set the key, but there are over a million records.

Is there another way of doing this please?

推荐答案

我不是100％肯定需要的T-SQL，但是可以创建自己的T-SQL.带有主键的新表，然后在旧表上运行光标，将在旧表中找到的每一行插入到新表中

I''m not 100% sure of the T-SQL you''d need, but you could create your new table complete with primary key and then run a cursor over your old table, inserting each row you find in the old table into the new one

另一种方法可能是创建一些新表表，每个表都有自己的主键，然后将数据从现有表复制到其他表中.新表的数量将反映您的数据的规范化，您选择多少表将取决于数据之间的关系.

Another approach may be to create a number of new tables, each with their own primary key and then copy the data from your existing table into these other tables. The number of new tables would reflect a normalizing of your data and how many you choose would be dependant upon how the data relates to each other.

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