How to use MySQL indexes rationally and optimize database performance? Design protocols that technical students need to know!

How to use MySQL indexes reasonably to optimize database performance? Design protocols that technical students need to know!

Introduction:
In today's Internet era, the amount of data continues to grow, and database performance optimization has become a very important topic. As one of the most popular relational databases, MySQL’s rational use of indexes is crucial to improving database performance. This article will introduce how to use MySQL indexes rationally, optimize database performance, and provide some design rules for technical students.

1. Why use index?
Index is a data structure used to speed up database queries. It can help the database system quickly locate the required data in massive data. Without an index, the database system needs to scan all records one by one, and such query efficiency is very low. The use of indexes can greatly improve query efficiency and reduce the time required for queries.

2. How to select index fields?

1. Uniqueness: Select unique fields as indexes, such as primary keys, unique constraint fields, etc.
2. Frequent queries: Select fields that are often used as query conditions as indexes. In practical applications, more frequent query conditions include user ID, product number, keywords, etc.
3. Data length: Choose shorter fields as indexes, because short fields can reduce the storage space of the index and improve query efficiency.

3. Index type

1. B-Tree index: It is the default index type of MySQL and is suitable for full value matching, range query and sorting operations. In most cases, B-Tree indexes are sufficient.
2. Hash index: suitable for equivalent queries, very fast. However, hash indexes cannot be used for range queries and sorting operations, and there are certain limitations for large data sets.
3. Full-text index: suitable for fuzzy query of text information. By using full-text indexing, efficient text search capabilities can be provided.

4. Index design rules

1. Don’t abuse indexes: Although indexes can improve query performance, they will also increase the cost of write and update operations. Therefore, don't create an index on every column. Reasonably determine which fields need to be indexed to avoid performance losses caused by too many indexes.
2. Combined index: When multiple fields are often queried together, you can consider using a composite index. Combined indexes can improve query efficiency and avoid the search operations of multiple separate indexes.
3. Avoid calculation of index columns: Try to avoid function calculations on index columns in query conditions, because this will cause the index to become invalid and make it impossible to use the index for fast queries.
4. Use a covering index: A covering index can be used when the query only needs to get data from the index without accessing other columns of the table. Covering indexes can reduce IO operations and improve query performance.
5. Regular maintenance of indexes: Indexes will change as data is added, deleted, and modified, so indexes need to be maintained regularly, including deleting indexes that are no longer used, rebuilding indexes, etc.

Conclusion:
Reasonable use of MySQL indexes is an important means to optimize database performance. By selecting appropriate index fields, selecting appropriate index types, and complying with index design specifications, the efficiency of database queries can be improved, system response time can be reduced, and user experience can be improved.

Design protocols for technical students: In order to ensure the stability and efficiency of database performance, technical students should have a deep understanding of the principles and usage of indexes, and follow the design protocols for optimizing database performance. At the same time, it is also necessary to regularly monitor database performance and timely optimize and adjust indexes based on actual conditions to ensure the stability and high availability of the database system.

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