1, Database operation
1) Select and create database syntax:
use database name
The rule of the use command is to switch if the corresponding database exists, and create if it does not exist
2) Deletion of database
3) View databases with permissions
show dbs or show databases
Note: when you use the use com ...
Posted on Sun, 05 Dec 2021 02:17:05 -0500 by SwiftlyTilting
1. Specific contents
JDBC (Java DataBase Connectivity) is a java database connection. In other words, it uses the Java language to operate the database. It turns out that we operate the database by using SQL statements on the console, and JDBC sends SQL statements to the database in Java language. JDBC (Java Data Base Connecti ...
Posted on Sun, 05 Dec 2021 00:40:10 -0500 by empnorton
The transaction message of rocketmq is used as a solution to distributed transactions on some occasions. Today, let's analyze the transaction message of rocketmq
1. Transaction message flow process
2. The producer sends a transaction message (half message)
3. The broker handles the half message
4. The producer executes a local tr ...
Posted on Sat, 04 Dec 2021 21:41:55 -0500 by sawade
1. AUFS and overlay / overlay 2
2. overlay structure
3. Joint mount
2, Written by dockerfile
1. Dockerfile structure consists of four parts
2. CMD and entrypoint
3. Write dockerfile
4. dockerfile optimization
Building nginx images
docker image hierarchy
Difference between CMD and EN ...
Posted on Sat, 04 Dec 2021 18:46:31 -0500 by keithschm
Tip: after the article is written, the directory can be generated automatically. Please refer to the help document on the right for how to generate it
This article is the author's study notes. It records in detail the author's understanding of SQL digital injection, and also introduces the complete process of using union joint q ...
1, Concept of distributed transaction
1. What is a transaction
A transaction can be regarded as a big activity. It consists of different small activities. These activities either succeed or fail.
2. Local affairs
Four characteristics of database transactions ACID:
A(Atomic): Atomicity ， All operations constituting a transact ...
Posted on Fri, 03 Dec 2021 19:07:35 -0500 by bache
Redis is short for Remote Dictionary Service; It is also a Remote Dictionary Service;
Redis is a memory database, KV database and data structure database;
Redis is widely used, such as Twitter, Blizzard Entertainment, Github, Stack Overflow, Tencent, Alibaba, JD, Huawei, Sina Weibo, etc. many small and medium-sized companies are also u ...
Posted on Fri, 03 Dec 2021 15:46:02 -0500 by shaunrigby
This article continues to introduce the main process and main details of memory flush on hregon, and how cacheflush handles flush requests.
How does cacheflush handle flush requests
Through the introduction of how to initialize cacheflush, we know that there are two queues and collections that store flush requests and their h ...
It is often said that reading source code is the only way for every excellent development engineer, but in the face of complex systems like TiDB, source code reading is a very huge project. For some TiDB users, starting from their daily problems, reading the source code is a good entry point. Therefore, we planned a series of articles on readin ...
Posted on Fri, 03 Dec 2021 02:28:23 -0500 by coffeecup
Last time I wrote about JPA, let's talk about Spring Data JPA
Spring Data JPA is a set of JPA application framework encapsulated by spring based on ORM framework and JPA specification. Developers can use very simple code to access and operate the database.
In daily use, Spring Data JPA development frees us from the operation of Dao layer, and ...
Posted on Fri, 03 Dec 2021 00:30:55 -0500 by beesgirl713