Database learning notes
MySQL database matters needing attention 1.where query=No, No== 2.MySQL The string subscript starts with 1, LIMIT Qualified query with subscript starting from 0 3,Teaching video sql Documents, salary yes varchar Type, so+0，express int type 4.image subject For this keyword, use``,`subject`,thatUTF-8...
Posted by tartou2 on Mon, 27 Sep 2021 09:30:20 +0530
Mybatis05 - one to many and many to one processing
10. Many to one processing Many to one understanding: -Multiple students correspond to one teacher -For students, it is a many to one phenomenon, that is, a teacher is associated with students! Database design CREATE TABLE `teacher` ( `id` INT(10) NOT NULL, `name` VARCHAR(30) DEFAULT NULL, PRIMUTF-8...
Posted by kaoskorruption on Mon, 27 Sep 2021 10:27:47 +0530
Apache Doris synchronizes data through external tables
Apache Doris synchronizes data through external tables Doris can create external tables accessed through the ODBC protocol. After creation, you can directly query the data of the external table through the SELECT statement or import the data of the external table through INSERT INTO SELECT. ThiUTF-8...
Posted by geon on Tue, 28 Sep 2021 15:33:53 +0530
Spring voice explicit transaction
entrance In Spring, we can start declarative transactions through @ enable transaction management; But in SpringBoot, we found that declarative transactions are enabled without this annotation. Why? The answer lies in the Spring.factories in the org.springframework.boot: Spring boot autoconfiguUTF-8...
Posted by likwidmonster on Thu, 30 Sep 2021 01:51:04 +0530
Explain @ Builder usage in Lombok
Builder uses creator mode, also known as builder mode. In short, it is to create an object step by step. It shields the details of the construction to the user, but it can finely control the construction process of the object. Basic use @The builder annotation generates a relatively complex buiUTF-8...
Posted by Tohou on Thu, 30 Sep 2021 02:03:31 +0530
Building and testing of read-write separation cluster for Windows 8 database
Thank you @ panthom_ Contribution made by W great God data Establishment of windows Dameng 7 read-write separation cluster Construction of read-write separation cluster on Dameng official website preface Because the company's business requires the use of domestic Damon database and the requiremUTF-8...
Posted by aman_batra on Thu, 30 Sep 2021 02:48:22 +0530
Deployment of self study notes on MySQL 8 official website MGR
Self study notes on MySQL 8 official website Chapter 1 deploying Mgr (MySQL group replication) preface It has been five years since MySQL 8 was launched on September 12, 2016. Its version has become mature and stable, and the industrial upgrading implementation schemes of major factories have bUTF-8...
Posted by pseudonym on Thu, 30 Sep 2021 07:52:05 +0530
iOS - use of FMDB for data persistence
preface Last article iOS - data persistence using SQLite database , this paper introduces how to use sqlite3 to operate SQLite database to realize addition, deletion, modification and query. However, in the process of coding, we found that sqlite3 needs to call a large number of C language funcUTF-8...
Posted by PatelNehal on Thu, 30 Sep 2021 08:32:10 +0530
Mybatis actual combat: one to many relationship
One background 1.1 examples The company has several employees. At this time, the relationship between the company and its employees belongs to a one to many relationship. Based on the above information, we can create two tables: company information and employee information. The company table fUTF-8...
Posted by gushy on Fri, 01 Oct 2021 02:37:02 +0530
Deploy the SpringBoot project to the server
1, Server environment preparation 1. Install and configure JDK Use FileZilla to upload jdk-8u161-linux-x64.tar.gz to the mnt folder of the server mkdir /opt/modules/ Extract to the new folder tar -xf /tmp/jdk-8u161-linux-x64.tar.gz -C /opt/modules/ Configure environment variables vi /etc/profiUTF-8...
Posted by gandelf1000 on Sat, 02 Oct 2021 03:23:37 +0530