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This article will explain in detail what is the use of MySQL index for you. The editor thinks it is very practical, so I share it with you as a reference. I hope you can get something after reading this article.

The establishment of MySQL index is very important for the efficient operation of MySQL, and the index can greatly improve the retrieval speed of MySQL.

For example, if the properly designed MySQL that uses the index is a Lamborghini, then the MySQL without the design and use of the index is a human tricycle.

Indexes are divided into single-column indexes and combined indexes. A single-column index, that is, an index contains only a single column, and a table can have multiple single-column indexes, but this is not a combined index. A composite index, that is, an index contains multiple columns.

When creating an index, you need to make sure that the index is the condition that is applied to the SQL query statement (usually as a condition of the WHERE clause). [specific operation methods you can refer to the MySQL video tutorial or MySQL manual! ]

In fact, an index is also a table that holds the primary key and index fields and points to the records of the entity table.

All of the above talk about the benefits of using indexes, but excessive use of indexes will lead to abuse. Therefore, the index also has its disadvantages: although the index greatly improves the query speed, it slows down the speed of updating the table, such as INSERT, UPDATE, and DELETE on the table. Because when updating the table, MySQL not only saves the data, but also saves the index file.

Create an index file that takes up disk space.

This is the end of this article on "what is the use of MySQL index". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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