View is a virtual table (non-real), whose essence is to get dynamic data sets according to SQL statements and name them. Users can get the result set by using only the name, and use it as a table.
nid &g ...
Posted on Mon, 03 Jun 2019 21:39:41 -0700 by Cochise
From MySQL 5.7 ref: 18.104.22.168 Derived Tables
8. Derived Table
Derived tables are expressions used to generate tables within the scope of a query's FROM clause.
For example, a subquery in the FROM clause of a SELECT query is a derived table.
SELECT ... FROM (subquery) [AS] tbl_name ...
The [AS] tbl_name clause is required because ...
Posted on Sun, 02 Jun 2019 09:36:59 -0700 by supermerc
Introduction to spring-data-Jpa First we know JPA(Java Persistence API), the Chinese name is Java persistence layer Api, a JDK 5.0 annotation or XML describing object-relational table mapping relationship, and the runtime entities Object Persistence To the database.It was created to integrate third-party ORM framework and establish unified ...
Posted on Sun, 02 Jun 2019 09:33:06 -0700 by ben14
Initialize swarm manager and make network card address
docker swarm init --advertise-addr 192.168.10.117
Force the deletion of the cluster, if it is a manager, you need to add force
docker swarm leave --force
docker node rm docker-118
View the connection token of swarm worker
docker swarm join-token worker
View the co ...
Posted on Fri, 31 May 2019 11:46:37 -0700 by bravo14
Generally stored under / var/lib/mysql
1. View mysql's current data storage location
[root@dlzx ~]# mysqladmin -u root -p variables |grep datadir
| datadir | /usr/local/mysql/data/ |
Posted on Mon, 27 May 2019 14:18:10 -0700 by EvilSupahFly
date: 2017-9-4 01:25:27
title: php file export full records
Almost all of phper's needs come from the "management backstage", of which "file export function" is almost indispensable. After three years of phper, almost three years of this requirement has been followed. Recently, although I'm writing a server, since the little ...
Posted on Mon, 27 May 2019 12:35:55 -0700 by flyersman
Mycat's role in applications is described as follows:
Mysql master is responsible for reading and writing for master library and Mysql slave is responsible for reading from slave library. In this way, programmers can only care about business code compilation, without worrying about load balancing of back-end database cluster, separa ...
Posted on Mon, 27 May 2019 10:56:43 -0700 by robert.access
1 /*Table structure for table `stuscore` */
3 DROP TABLE IF EXISTS `stuscore`;
5 CREATE TABLE `stuscore` (
6 `id` int(11) NOT NULL AUTO_INCREMENT,
7 `name` varchar(20) DEFAULT NULL,
8 `subject` varchar(20) DEFAULT NULL,
9 `score` varchar(20) DEFAULT NULL,
10 `stuid` varchar(10) DEFAULT NULL,
11 PRIMARY KEY (`id`)
Posted on Sun, 26 May 2019 14:02:09 -0700 by p2grace
1. Create two virtual machines
2. Install mysql. Here I install binary MySQL 5.5 through script
####One button installation Mysql-5.5 Edition####
#### Query whether mysql users exist####
#create group if not exists
Posted on Sun, 26 May 2019 10:36:14 -0700 by sixseven
Prerequisites and Needs
How to realize top in oracle
Usage of ROW_NUMBER OVER Analysis Function
How to convert control into specified value
Final Final Edition sql
Prerequisites and Needs
Main table: ag_ba_old_base
From table: AG_BA_OLD_MEDICAL
Dictionary table: jz_dictionary
The field ag_ba_old_base_id in ...
Posted on Sat, 25 May 2019 16:48:30 -0700 by hex