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Editor to share with you what there are three ways to delete data in MySQL, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's learn about it!

There are three ways to delete data in MySQL: delete, drop, and truncate. These three methods are easy to use, but the principles and considerations behind them are probably not clear to most developers. Let me explain the following principles and precautions.

1. Delete

Delete is a database DML operation language. When deleting data, it will only delete the data, not the table structure of the table in which the data is located. When deleting the data, it will execute the transaction and trigger trigger. And if the database engine you are using is InnoDB, then MySQL will only mark the data as deleted instead of actually deleting the data when performing the delete data operation, so in this case if you use Delete to delete the data, you will find that the table size has not changed.

But when your database engine is MyISAM, executing the delete from table statement will really delete the data in the table and free up space. If you want the MyISAM engine to achieve the effect of false deletion by the InnoDB engine, you need to add a Where condition to the Delete statement, such as delete from user where age.

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