Grouping operation of MongoDB, associative set query (multi table query)

Now, we have a set (data table), whose structure and code are as follows: db.tb5.insert([{"name":"Zhang San","date":"2018/6/1","score":50}, {"name":"Li Si","date":"2018/6/1","score":57}, {"name":"Wang Wu","date":"2018/6/2","score":64}, {"name":"Zhang San","date":"2018/6/3","score":78}, {"name":UTF-8...

Posted by ahundiak on Wed, 19 Jan 2022 18:33:47 +1030

Details determine success or failure of MySQL MHA deployment

1. What is MHA • MHA (MasterHigh Availability) is a set of excellent software for failover and master-slave replication in MySQL high availability environment. • the emergence of MHA is to solve the problem of MySQL single point. • during MySQL failover, MHA can automatically complete the failUTF-8...

Posted by ShogunWarrior on Sat, 22 Jan 2022 09:11:46 +1030

Come in and have a look. There's something you want

MongDB install https://www.mongodb.com/try/download/community Mongdb vs RDS Database : DatabaseCollection : TableDocuments : Row Create database use dbName; Create collection db.createCollection(); CRUD Insert(Create) In mongdb, the write operation of a document is atomic db.collection.insertOUTF-8...

Posted by kpmonroe on Sun, 23 Jan 2022 02:49:17 +1030

[MongoDB]3. springboot integration mongodb field test

1. Pretend it's a preface In the previous blog, I wrote about the basic command operation of MongoDB Shell. In development, we usually use code to operate the database. For Java, there are many ways to operate the database. One is to use Java's native JDBC interface to download MongoDB's jdbc dUTF-8...

Posted by krishna.p on Wed, 26 Jan 2022 14:34:54 +1030

[Longyuan war virus] - Checkin completely reappears

1, Foreword This is a game on November 7, 2021. It should be an expired game for CTFers. So why do I choose to repeat this question? 1. Main reasons It's more memorable. This is the first time I realized that I "met a go language question". 2 my persistence In the three-month learning process,UTF-8...

Posted by wpsa on Fri, 28 Jan 2022 19:56:55 +1030

CentOS 7.6 64bit installation, building MongoDB stand-alone replica set, configuring Spring Boot and starting the whole process of transaction

Install main program Download address of Linux Installation Package: CSDN,Code cloud Upload the compressed package to Linux and unzip it to the current directory: [root@centos ~]# tar -xvf mongodb-linux-x86_64-4.0.10.tgz Move the extracted folder to the specified directory: [root@centos ~]# mvUTF-8...

Posted by Corvin on Fri, 28 Jan 2022 20:10:25 +1030

MongoDB replica set (one active and one standby + arbitration) environment deployment

https://www.cnblogs.com/kevingrace/p/7881496.html, https://blog.csdn.net/com_it/article/details/84702046 The MongoDB replica set is a master-slave cluster with failover. It evolved from the existing master-slave mode, adding automatic failover and automatic recovery of node members. There is noUTF-8...

Posted by jsladek on Sat, 29 Jan 2022 18:30:54 +1030

Mongodb basic operation

Database operation establish Select and create the syntax format of the database: If the database does not exist, it is created automatically. For example, the following statement creates a spitdb database: use spitdb see View the database commands currently in use show dbs or show databases > UTF-8...

Posted by eroticheretic on Fri, 04 Feb 2022 17:18:48 +1030

How to make database work efficiency ten times

This translation is two in one, and the original author is Yury Selivanov( @1st1 )And Elvis Pranskevichus( @elprans),A Path to a 10x Database It was released on June 18, 2019, and the second half is extracted from the report released on April 11, 2019 , for a long time, soUTF-8...

Posted by agret on Sat, 05 Feb 2022 00:19:57 +1030

Spring Data MongoDB tutorial of SpringBoot series

Spring Data MongoDB tutorial of SpringBoot series 1. MongoDB download and installation Because I didn't buy a linux server, this blog only installs window to learn. You can click Official website download link Download and skip the installation process The client software can choose a higher veUTF-8...

Posted by Mehdi on Mon, 07 Feb 2022 16:59:07 +1030