Four isolation types of MYSQL transactions and source code interpretation and practical application in PHP framework Yii2

There are no weak people in life, only those who are unwilling to work hard. 1, What is a transaction Transaction is the basic unit of concurrency control. The so-called transaction is a sequence of operations. These operations are either executed or not executed. It is an inseparable work unit. Transaction is the unit for maintaining ...

Posted by ankrah on Sun, 19 Dec 2021 14:17:25 +0100

MySQL storage function, worth a visit

Write in front: follow Master Kang of station B to learn the notes summary and self summary of mysql. 1. Create storage function Syntax format: CREATE FUNCTION Function name(Parameter name parameter type,...) RETURNS return type BEGIN Function body #There must be a RETURN statement in the function body END explain: Parameter li ...

Posted by Lord Sauron on Sun, 19 Dec 2021 12:21:00 +0100

Shang Silicon Valley JDBC core technology (New jdbc)

JDBC introduction JDBC(Java Database Connectivity) is a common interface (a set of API s) independent of a specific database management system and general SQL database access and operation. It defines the standard Java class libraries used to access the database (java.sql,javax.sql). These class libraries can be used to access database resourc ...

Posted by brandonschnell on Sun, 19 Dec 2021 08:14:36 +0100

Redis6 video course in Silicon Valley

Introduction to NoSQL database technological development Classification of Technology Solve functional problems: Java, Jsp, RDBMS, Tomcat, HTML, Linux, JDBC, SVNSolve the problem of Extensibility: Struts, Spring, Spring MVC, Hibernate, MybatisSolve performance problems: NoSQL, Java thread, Hadoop, Nginx, MQ, ElasticSearch NoSQL database N ...

Posted by saltedm8 on Sun, 19 Dec 2021 05:35:52 +0100

Several cases of index failure

I Several cases of index failure The index does not always take effect. For example, the following situations will lead to index invalidation If there is or in the condition, it will not be used even if some of the conditions are indexed (this is why or is used as little as possible) (user_id is not indexed) Note: to use or and make the index ...

Posted by EverToDesign on Sun, 19 Dec 2021 04:46:42 +0100

Mysql database management (all you want is here!!)

1, MySQL database management 1.1 warehouse and table Database – > data table – > row (record): information used to describe an object Column (field): an attribute used to describe an object 1.2 common data types intintegerfloatSingle precision floating point 4-byte 32-bitdoubleDouble precision floating point 8-byte 64 ...

Posted by Tea_J on Sat, 18 Dec 2021 23:40:54 +0100

10592 words, 475 lines, byte beating interview questions and answers Java

<property name="password">123456</property> <property name="schemas">ITCAST</property> 123456 ITCAST true ``` After configuration, restart MyCat service; Description of attribute meaning: checkSQLschema When the value is set to true Time, If we execute the statement"select * from test01.user ;" Statement time, MyC ...

Posted by slightlyeskew on Sat, 18 Dec 2021 16:12:06 +0100

Mybatis, this is enough, simple and comprehensive! (recommended Collection)

Mybatis 1. Introduction MyBatis was originally a part of apache Open source project iBatis, 2010 project Migrated from apache software foundation to [Google Code]( https://baike.baidu.com/item/google Code / 2346604) and renamed MyBatis. Moved to in November 2013 Github. iBATIS comes from the combination of "internet" and "aba ...

Posted by fourlincoln10 on Sat, 18 Dec 2021 10:44:54 +0100

SpringBoot pit avoidance guide -- building a data access layer

1, JDBC specification 1.1 introduction to JDBC JDBC is the full name of Java Database Connectivity. Its original design intention is to provide a set of unified standards that can be applied to various databases. This set of standards needs to be observed by different database manufacturers, and provide their own implementation schemes for JD ...

Posted by silviuchingaru on Sat, 18 Dec 2021 10:07:37 +0100

Redis download and installation (Linux download)

Redis download and installation (Linux download) 1. Environmental preparation Virtual machine version: VMware ® Workstation 16 ProLinux system: Centos7Remote command side: xshellFile transfer tool: SecureFXPortable 2.Redis installation 2.1 Redis compilation language Redis is developed in C language. To install redis, you need to downl ...

Posted by Plex on Sat, 18 Dec 2021 10:04:04 +0100