


The secret to database performance tuning: MySQL design conventions that technical students must understand!
The secret of database performance tuning: MySQL design protocols that technical students must understand!
Introduction: For many large applications and systems, performance is critical. The database is the core of these systems. In order to ensure the high-performance operation of the database, we need to reasonably design the database structure and use correct tuning techniques. This article will share some MySQL design rules to help technical students tune database performance.
1. Reasonable design of database structure
- Standardized naming of tables: Use meaningful names when naming tables, do not use names that are too long or too simple, so as to better Describe the meaning and content of the table.
- Make full use of data types: Choosing appropriate data types can reduce the storage space of the database and improve query and index efficiency. For example, for fields that do not need to store negative numbers, you might choose to use unsigned integers.
- Choose indexes correctly: Indexes are an important means to improve query efficiency, but too many or too few indexes will have a negative impact on performance. Appropriate fields should be selected as indexes based on query requirements and data characteristics, and avoid using too many indexes on tables that are frequently inserted and updated.
Sample code:
-- 创建表时指定字段类型和索引 CREATE TABLE user ( id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY, name VARCHAR(50), age TINYINT UNSIGNED, INDEX (age) );
2. Optimize query statements
- Avoid using SELECT *: Only selecting the required fields can reduce the amount of query data. Reduce database burden and improve query efficiency.
- Reasonable use of JOIN: JOIN operation is a commonly used operation in relational databases, but you need to pay attention to the performance impact when using it. You should try to avoid nesting JOIN multiple times and consider using subqueries or temporary tables to optimize multi-table related queries.
Sample code:
-- 避免使用SELECT * SELECT id, name FROM user; -- 使用子查询优化JOIN操作 SELECT a.id, a.name, b.age FROM user a INNER JOIN ( SELECT id, age FROM user_age WHERE age > 18 ) b ON a.id = b.id;
3. Reasonable use of transactions
- Use transactions when performing batch operations: When multiple write operations need to be performed, Placing these operations in the same transaction can improve efficiency and ensure data consistency.
Sample code:
-- 使用事务执行批量插入操作 START TRANSACTION; INSERT INTO user (name) VALUES ('Tom'); INSERT INTO user (name) VALUES ('Jerry'); COMMIT;
4. Set the database parameters reasonably
- Set the correct buffer size: According to the memory size of the system and the load of the database Depending on the situation, adjust the buffer size appropriately to ensure query performance.
- Set the correct number of connections: Set the maximum number of connections reasonably to avoid exhaustion of database resources due to too many connections.
5. Regular backup and optimization of database
- Regular backup of data: Regular backup of data can ensure the security and integrity of the data. At the same time, for large databases, the backup process is also It requires a certain amount of time and resources.
- Perform regular database optimization: Database optimization includes operations such as reorganizing tables, optimizing query statements, and adjusting database parameters, which can improve database performance and response speed.
Summary: Database performance tuning is a complex and meticulous process, which requires technical students to make reasonable adjustments in designing database structures, optimizing query statements, rationally using transactions, and setting database parameters. . Following the MySQL design convention can help us better tune database performance and ensure high-performance operation of the system. I hope that some of the MySQL design rules introduced in this article can help technical students in database performance tuning.
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