合并和更新主键 [英] Merge and update primary key

问题描述

我看了看，但没有找到解决看似简单问题的方法.

I looked, but didn't find a solution to what seems like a simple problem.

我有许多具有相同结构的表，并希望将它们合并.唯一的问题是它们都有一个id字段作为主键.主键中将有很多重复项. id最终是什么都无关紧要.如何合并所有表，以免丢失任何数据?

I have many tables with identical structure and want to merge them. The only problem is that they all have an id field as the primary key. There would be a lot of duplicates in the primary key. It doesn't matter what the id ends up being. How can I merge all the tables so I don't loose any data?

推荐答案

在新表中创建一个AUTO_INCREMENT字段，并从值列表中将其忽略:

Create an AUTO_INCREMENT field in the new table and omit it from the list of values:

CREATE TABLE NEW_TABLE (id INT NOT NULL AUTO_INCREMENT PRIMARY KEY, col1 …, col2 …, …);

INSERT
INTO    new_table (col1, col2, …)
SELECT  col1, col2
FROM    old_table_1
UNION ALL
SELECT  col1, col2
FROM    old_table_2
UNION ALL
…

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