Programming VIP

JDBC Concept: Java DataBase Connectivity - Java database connection, Java language operation databaseJDBC essence: in fact, it is an officially defined set of rules for operating all relational databases, that is, interfaces. Each database manufacturer implements this interface and provides database driver jar package. We can use this set of i ...

1. Configure YUM source 1.1 download mysql source installation package [root@chris /]# wget http://dev.mysql.com/get/mysql57-community-release-el7-11.noarch.rpm 1.2 installing mysql source [root@chris /]# yum localinstall mysql57-community-release-el7-11.noarch.rpm 1.3 check whether the mysql source is successfully installed [root@chris ...

InnoDB logical storage unit is mainly divided into table space, segment, area and page 1. Tablespace All data of InnoDB is stored in table space, which is divided into system table space and independent table space MySQL5. After 7, there are temporary table spaces and general table spaces 1) SYSTEM tablespace The system table space is main ...

First, insert multiple pieces of data. Options: foreach loop insertSplicing sql, one executionInsert using batch function 1. foreach insertion First obtain the list, and then perform a database operation for each piece of data to insert data: @SpringBootTest @MapperScan("com.aphysia.springdemo.mapper") class SpringdemoApplicationTests { ...

1, SELECT statement basis select <Listing>, from(Table name)； where <Conditional expression> Correlation rule An asterisk (*) means all columns.Line breaks can be used in SQL at will, which does not affect the execution of statements (but empty lines cannot be inserted).When setting Chinese aliases, you need to use double qu ...

Previous: MySQL KEY partition and LINEAR KEY partition Partitions in MySQL do not allow null as the value of partition expressions, whether column values or user provided expressions. Even if NULL is allowed as the value of an expression, an integer must be returned. It is important to remember that null is not a number. MySQL partition implem ...

This article is an accident troubleshooting note for deadlock in the production environment. You can learn from reading this article:What are the locks commonly used in Innodb?Are locks compatible or incompatible?What is the locking principle of Update statement?Let's restore the scene of the accident with meOperation backgroundMySQL 8.0.20Enab ...

*Blog home page ——Xiaojie's blog home page to cheer *Welcome to pay attention to likes collection messages *Just learned, if ## title is wrong, please correct it! Function table: 1. Statistical total functioneffectCOUNT(*)Returns the number of rows of records that meet the criteriaCount (column)Returns the number of rows, but ...

Spring 1. Introduction to spring framework Spring, born in 2002, was created by Rod Johnson. Spring framework is an open source, lightweight project management framework that integrates many design patterns. Committed to JAVAEE lightweight solutions. Compared with the original framework, the spring framework is essentially different fro ...

The original content of GreatSQL community cannot be used without authorization. Please contact Xiaobian and indicate the source for reprint.Experimental environmentGreatSQL 8.0.25 InnoDB1. Introduction to index push down1. Index Condition Pushdown is short for ICP.2.MySQL5. Version 6 introduces the function for optimizing queries.3. Under some ...