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This article mainly introduces the mysql is not equal to how to express the relevant knowledge, the content is detailed and easy to understand, simple and fast operation, with a certain reference value, I believe that after reading this mysql does not mean that how to express the article will have something to gain, let's take a look at it.

In mysql, it does not mean that it can be expressed as "" or "! =", but it is generally expressed as "", because "" works in any SQL, has strong portability, and is fast in query.

The operating environment of this tutorial: windows10 system, mysql8.0.22 version, Dell G3 computer.

In mysql, it is not equal to how to express.

Judgment symbols are commonly used in MySQL, but they are not equal to the more commonly used symbols. Here are three symbols that are not equal to them.

The earliest usage in which the symbolic meaning is not equal to, the portability is better than the following two! = later added to MySQL, similar to Java and other programming languages, it is not equal to not innot in followed by data, indicating that it is not in the data.

It is recommended in MySQL to indicate that it is not equal to. Why? Because the portability is strong, because the query speed is fast. There is a question on leetcode, which is the question asked by the cinema. The title is as follows:

In fact, very simple, query description non-boring and id non-even number, the query results can be sorted using order by, but in the query description non-boring to use not equal to judge, the following is my use of three different query time comparison

You can see that it is still faster, so it is recommended to use it to indicate that it is not equal to.

This is the end of the article on "what is not in mysql". Thank you for your reading. I believe you all have a certain understanding of the knowledge that "mysql is not equal to how to express". If you want to learn more knowledge, you are welcome to follow the industry information channel.

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