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1. Download from the official website Address: https://dev.mysql.com/downloads/mysql/ Select 8.0 Version 25 2. Software decompression 2.1 selection of location One thing to note: try to avoid Chinese in the decompression path, otherwise an error will be reported later. 3. Configuration file 3.1 create my INI file Change the text suf ...

summary Index is a data structure used by the storage engine to quickly find records. Through the rational use of database index, the access performance of the system can be greatly improved. Next, it mainly introduces the index types in MySql database and how to create a more reasonable and efficient index skills. Note: This is mainly for ...

4. Query 4.1 aggregate query 4.1. 1 aggregate function Common operations such as total statistics and average calculation can be realized by using aggregation functions. Common aggregation functions include: functionexplaincountReturns the number of queried datasumReturns the sum of the queried data. It is not a number. It is meaningles ...

Regular expressions are mainly used to query and replace text content that conforms to a certain pattern (rule). They are powerful and flexible. They are often used in very complex queries. Compared with LIKE, the matching rules are very comprehensive. In MySQL, use the REGEXP keyword to specify the character matching pattern of regular expres ...

Welcome to the MySQL technical articles shared by the great SQL community. If you have any questions or want to learn, you can leave a message in the comment area below. After seeing it, you will answer itIn the MGR test, after artificially creating the disk full problem, the node is OO m killedProblem descriptionIn MySQL 8.0 26 vs GreatSQL 8.0 ...

Because the character set is related to the comparison rule, the comparison rule will be automatically transformed into the corresponding one after modifying the character set. On the contrary, the character set will also change after modifying the comparison rule. mysql> SHOW VARIABLES LIKE 'character_set_server'; +----------------------+- ...

preface In the previous two issues, we completed the creation of Mysql database tables and the design of Html interface. In this issue, we will complete the last part - the design of user login function. It mainly uses: JDBC, Servlet, Java, object-oriented and other knowledge Its basic principle: after the login interface is submitted, a ser ...

Relational structured storage has some disadvantages, because it needs to define all columns and their corresponding types in advance. However, in the process of business development, it may be necessary to expand the description function of a single column. At this time, if the JSON data type can be used well, the boundary between the storage ...

1, Software installation 1.1 MySQL installation Download the installation package mysql-8.0 23-1. el7. x86_ 64.rpm-bundle. tar. gz. After decompression, the installation process shall be carried out in the following order: (1) mysql-community-common[dongxw@localhost mysql]$ sudo rpm -ivh mysql-community-common-8.0.23-1.el7.x86_64.rpm (2) My ...

1 Introduction 1.1 background For the InnoDB storage engine, generally, a table corresponds to an FRM file, which saves the table structure and index. When the amount of data is large (generally more than ten million records), the performance of the database will begin to decline. At this time, you can consider partitioning or table splitting t ...