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1, Error reporting page 2, Error reporting reason This error occurs in MySQL version 5.7 and above: The default sql configuration for MySQL version 5.7 is sql_mode = "ONLY_FULL_GROUP_BY", this configuration strictly implements the "SQL92 standard". When upgrading from 5.6 to 5.7, most of them choose to adjust SQL for syn ...

Basic operation of JDBC In order to reuse the code and improve the development efficiency, it is very necessary to design the addition, deletion, modification and query of JDBC database. JDBC data operation steps are generally divided into the following five steps: 1, Load database driver class Class.forName("com.mysql.cj.jdbc.Driver"); ...

Function 1. Functional overview Use Python to complete a program to add or delete student information about MySQL database, mainly involving knowledge points: cursor use, SQL statements, and the basic knowledge previously learned. 2. Mind Mapping The idea has been put into practice 2. Start Practice Pre-war preparation You need to f ...

Transaction: understanding is a processing unit. This processing unit may contain deleted and modified operations that need to be processed. It is necessary to ensure that the processing unit is successfully completed or not executed at all. Transaction characteristics: atomicity, consistency, isolation and persistence Transactions are divide ...

1. Structure creation create Structure type structure name structure description; 2. Display structure show Structure type (plural) Display structure creation details: show create Structure type and structure name; 3. Data operation (data sheet) Add data: insert into Table name values View data: select from Table name Update data: updat ...

Tip: the project address is at the end of the article preface Today, senior students share a graduation design project: Development and design of infant product sales system based on SSH Using tomcat server and mysql database development tool eclipse, the project contains source code, supporting graduation thesis, defense materials an ...

Note: the official document of superset does not support Windows system. I started to use windows, and there was an error in the configuration thumbnail later. OS: Ubuntu20.04 Superset: 1.3.2 This is the problem I encountered in the installation and the information collected through query. The solutions to some problems may not be suitab ...

catalogue catalogue 1, System configuration optimization 1. Increase mysql memory 2. Reduce the number of disk writes Extracurricular knowledge 1. mysql data storage procedure: 2. What are redo log and undo log? 3. Data preheating 3.1. Data preheating script 3.2. Execute the command: 3.3 execute the command when data preheating is re ...

I brief introduction MyCat is an open source distributed database system and a server that implements MySQL protocol. Front end users can regard it as a database agent and access it with MySQL client tools and command line, while its back end can communicate with multiple MySQL servers using MySQL native protocol or with most mainstream databa ...

[the most complete MySQL summary in history] MySQL super detailed notes This article mainly introduces what MySQL is, its classification, SQL commands, MySQL installation precautions, classification and common commands in MySQL, Including: data query (basic query, sort query, condition query, time query, string query, aggregate function, gr ...