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[summary] if the server where CentOS is located is limited to security reasons and the customer does not configure us to access the Internet, how to install the PostgreSQL database? This article will explain in detail how to install PostgreSQL12 database offline on CentOS7 system through specific steps. 1 offline installation package preparati ...

1, Annotation development 1.1 comparison between annotations and xml xml: as a configuration file Advantages: it can extract content (decoupling), clear configuration, convenient positioning and easy to findDisadvantages: complicated configuration Note: xml development can be replaced Advantages: fast development speed and no cumbersom ...

2021SC@SDUSC hbase source code analysis (x) HFile analysis (2) 2021SC@SDUSC 2021SC@SDUSC 2021SC@SDUSC 2021SC@SDUSC HFileBlock HFileBlock mainly includes two parts: BlockHeader and BlockData. BlockHeader mainly stores Block related metadata, and BlockData is used to store specific data. The core field in Block metadata is the BlockType ...

Author: threedaymanSource: Hang Seng LIGHT cloud communityBasic conceptsdatabaseoracle database is the physical storage of data. Including data file ORA or DBF, control file, online file, log file and parameter file. oracle has only one database, which is managed by users. The process of creating a database in mysql database is to create a data ...

Basic operation of MongoDB learningThe aggregation operation of mongo is similar to the query of mysqlSQL operations / functionsmongodb aggregation operationwhere$matchgroup by$grouphaving$matchselect$projectorder by$sortlimit$limitsum()$sumcount()$sumjoin$lookupThe following examples are compared with sqlThe following is a basic structure for ...

192.168.80.51Main db01192.168.80.11From web04192.168.80.9From web03 1. Cluster preparation To realize master-slave, please back up the data first First, a single node redis has been installed Single node installation https://blog.csdn.net/ncnhhm/article/details/121443981 Master node profile daemonize yes bind 192.168.80.51 port ...

prefaceAs the data structure of Go core and the communication mode between Goroutine, Channel is an important structure supporting the high-performance concurrent programming model of Go language. This section will introduce the design principle, data structure and common operations of pipeline Channel, such as Channel creation, sending, receiv ...

1, Environment deployment   192.168.113.129   193.168.113.130     For the binary deployment method of mysql5.7, see mysql5.7 binary deployment   2, mysql replication based on binary log points 1. Create a replication account on mysql master-slave >create user slave@'192.168.113.%' identified by '123456'; 2. Authorize the account t ...

2021SC@SDUSC catalogue Hash index In addition to using B-Tree index, postgreSQL can also use hash index. Hash index has faster query speed. This article mainly explains the principle of hash index, compares it with B-Tree, and analyzes the relevant data structure of hash index in the source code. Hash indexing principle Hash table The ...

New bee mall project notes 1. Start the project and access the api online documentation http://localhost:8080/swagger-ui.html [the external chain image transfer fails. The source station may have an anti-theft chain mechanism. It is recommended to save the image and upload it directly (img-ge9fugsh-163811491017) (C: \ users \ Chen \ appdata ...