MySql notes-03 data manipulation language (DML)
Data manipulation language (DML)
1. Concept
Data manipulation language (DML), through which users can realize basic operations on the database. For example, query, insert, delete and modify the data in the table. However, there are three main forms of DML: data insertion, modification and deletion
2. Insert data
Insert statement ...
Posted by Gomesh on Thu, 31 Mar 2022 00:08:34 +0300
Design and implementation of online furniture mall platform based on Java Web + springboot (java+springboot+mysql+ssm)
Design and implementation of online furniture mall platform based on Java Web + springboot (java+springboot+mysql+ssm)
Main technologies: springmvc, springboot, mybatis, mysql, jQuery, layui and other technologies Specific functional modules:
(1) User registration and login functions:
① User registration function: visitors to the website reg ...
Posted by markts on Wed, 30 Mar 2022 18:49:38 +0300
MySQL 8 builds MHA with one master and two slaves
1, Introduction
MHA (Master High Availability) is a MySQL high availability solution. It is a management tool developed in perl language. It polls and detects the availability of MySQL master nodes, finds faults, automatically transfers faults, selects a slave node to be promoted to a new master node, replaces the old master node and continues ...
Posted by Soogn on Tue, 29 Mar 2022 18:19:02 +0300
day 05 DQL data query language --- connection query --- enter the room
Because sql statements are not case sensitive, all commands in this article use lowercase for convenience
Previous contents
day 01 first knowledge of Mysql and DDL data definition languageday 02 DML data operation languageday 03 DQL data query language -- a first glimpseday 04 DQL data query language - single table query - a slight succ ...
Posted by kampbell411 on Tue, 29 Mar 2022 07:33:25 +0300
Shandong University Project Training - map circle system - APP
Basic configuration settings and partial database creation
1, Basic configuration settings
About the basic configuration, it is mainly about solving cross domain problems and connecting to the database.
1. Solve cross domain problems
The IP address and port number of the front-end wechat applet and App are different from those of the Spring ...
Posted by bull on Sun, 27 Mar 2022 19:10:53 +0300
mysql stored procedure
MySQL stored procedure0. Environmental description:Softwareeditionmysql5.6HeidiSQL 1. InstructionsStored procedure is an important object of the database. It can encapsulate the set of SQL statements, can be used to complete some complex business logic, and can input and output parameters (similar to the writing of methods in java).When creatin ...
Posted by poisa on Sat, 26 Mar 2022 18:42:07 +0300
Detailed and complete knowledge of sql statements
Modify database table
Modify table name:
alter table Old table name rename as New table name
Add table fields
alter table Table name add Field column properties
For example: alter table student age int(11)
Modify the fields of the table
Modify constraints
alter table Table name modify Field column properties[];
For example: ...
Posted by jyushinx on Sat, 26 Mar 2022 12:26:12 +0300
2021 Centos 7 installs mysql through the terminal, with basic operation and detailed explanation, and interacts with Python (with code)
This blog is a follow-up to (). After crawling the data back, I wanted to directly turn it into excel, which is simple and convenient, but when I thought about how we are also programmers and can't be lazy, I put a database on the virtual machine and wrote a blog 😃
1. First look at the system version, Centos 7 2. wget obtains the mysql instal ...
Posted by MrXander on Sat, 26 Mar 2022 07:20:38 +0300
MySQL knowledge summary (Part 9) database driver + detailed explanation of environment configuration + JDBC program instance + detailed explanation of Connection class, Statement class and ResultSet class
preface: This article learned from: https://www.bilibili.com/video/BV1NJ411J79W?p=38 Make this note to help deepen your impression and facilitate future review
1, Database driven
The concept of driver here is the same as that heard in ordinary times. For example, the sound card purchased in ordinary times cannot be used when the network ...
Posted by jakobdoppler on Sat, 26 Mar 2022 06:12:24 +0300
Using python and MySql for storage encryption
Source download http://www.byamd.xyz/hui-zong-1/
Python 2.7IDE Pycharm 5.0.3PyMySQL 0.7.6MySQL 5.7MySQL Workbench 6.3
Application scenario
If the database is temporarily stored in a third party, and the stored data does not want to be seen by the third-party database administrator, and the message involves privacy and can only be seen ...
Posted by satheshf12000 on Sat, 26 Mar 2022 04:59:26 +0300