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This article is mainly about what will happen if the mysql primary key is empty. If you are interested, let's take a look at this article. I believe it will be of some reference value to you after reading that the mysql primary key is empty.

A database primary key is a column or a combination of columns in a table whose values uniquely identify each row in the table. One or more of these columns become the primary key of the table, through which the physical integrity of the table can be enforced. When you create or change a table, you can create a primary key by defining a PRIMARY KEY constraint, a table can only have one primary key constraint, and the columns in the primary key constraint cannot be null, and because the primary key constraint ensures unique data, identity columns are often defined.

The role of the primary key:

1. As can be seen from the above definition, the primary key is used to uniquely identify a row of data in a database table.

2. As an object that can be effectively referenced by a foreign key.

So can the mysql primary key be empty?

Be careful! The primary key can never be null!

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