将自增主键插入现有表

问题描述

我正在尝试更改一个没有主键和 auto_increment 列的表.我知道如何添加主键列，但我想知道是否可以自动将数据插入到主键列中(我已经在数据库中有 500 行并想给它们 id，但我不想手动执行).有什么想法吗?非常感谢.

I am trying to alter a table which has no primary key nor auto_increment column. I know how to add an primary key column but I was wondering if it's possible to insert data into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it manually). Any thoughts? Thanks a lot.

推荐答案

添加 PRIMARY KEY 列的 ALTER TABLE 语句在我的测试中正常工作:

An ALTER TABLE statement adding the PRIMARY KEY column works correctly in my testing:

ALTER TABLE tbl ADD id INT PRIMARY KEY AUTO_INCREMENT;

在为测试目的创建的临时表上，上述语句创建了 AUTO_INCREMENT id 列并为表中的每个现有行插入了自动递增值，从1.

On a temporary table created for testing purposes, the above statement created the AUTO_INCREMENT id column and inserted auto-increment values for each existing row in the table, starting with 1.

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