Six policies for improving MySQL database query speed

MySQL databaseIn the query process, we can take some measuresImproves query speedTo improve SQL Performance. This article mainly introduces six policies to speed up MySQL database queries. Let's take a look at them!

Policy for improving MySQL query speed:

1. Table design must be optimized, with the least redundant data and less connection queries. If the complex connection and subquery are used in practical applications, the design of the data table must be reconsidered.

2. use char instead of varchar as much as possible, because strings with a fixed length are faster to use. as hard disk capacity increases today, it is worthwhile to sacrifice storage space and increase the query speed.

3. Simplify the permission to increase the query speed. If you want to perform a lot of permission verification before a query, the query speed will slow down. Try to use root logon in mysql and the new user logon speed with permission control, as you can see, the root login will suddenly enter, while the normal user login will always be delayed.

4. Table optimization. If a table has been used for a period of time, the data will become fragmented as the update and deletion operations occur, which will also increase the time it takes for the physical search in the table. What you need to know is that in the mysql underlying design, the database will be mapped to a directory with a certain file structure, while the table will be mapped to a file. Therefore, disk fragments are very likely to occur. Fortunately, in mysql, we can fix it using the following statement:

 
 

  
  
optimize table tablename 
 
 

Or

 
 

  
  
myisamchk -r tablename 
 
 

5. Using indexes, you can use indexes where you need to increase the query speed to simplify the index. Do not create indexes that are not used for queries. You can analyze the issue by running the explain command.

6. Use the default value to use the default value of the column as much as possible. Data is inserted only when the default value is different. This reduces the time spent executing the insert statement.

The policy for improving MySQL database query speed is introduced here. If you want to learn more about the MySQL database, you can refer to the article here: http://database.51cto.com/mysql/, and I believe it can be taken for you!