How to optimize query performance in SQL Server

There are several methods to optimize query performance in SQL Server, including:

1. Creating appropriate indexes: By creating indexes on columns frequently used in queries, the query speed can be accelerated. Indexes can reduce the number of scans in the database, thereby improving query efficiency.
2. Optimize your queries by avoiding unnecessary ones, reducing redundant fields and conditions, and optimizing the execution plan of your query.
3. Choose the appropriate data type: Selecting the right data type can reduce storage space and improve data retrieval speed.
4. Avoid joining large tables: try to avoid joining queries between large tables, consider using subqueries or temporary tables to optimize query performance.
5. Using stored procedures can reduce network transmission costs and improve query performance.
6. Cache query results: To improve query speed for frequently accessed data, cache technology can be used.
7. Regularly maintaining the database, such as rebuilding indexes and updating statistics, can help ensure stable performance.