The project needs to back up the database regularly. Here are your own operation notes
1. Check the disk space
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/vda1 40G 3.6G 34G 10% /
tmpfs 16G 0 16G 0% /dev/shm
This is my current situation of linux server. I don't know why it's like this (I'm ...
Posted by joozt on Sat, 02 May 2020 07:56:12 -0700
Project Description: in the wechat applet, log in and verify with the spring boot operation database. I use spring boot to integrate the mybatis plus and mysql operation database
1. Preparation before development
1.1 prior knowledge
SpringBoot simple Basics
1.2 environmental parameters
Development tools: IDEA
Basic environm ...
Posted by Ixplodestuff8 on Sat, 02 May 2020 02:21:48 -0700
DBUtils is a module of Python used to implement database connection pool, and allows thread safe packaging of non thread safe database interface.
Two modes of connection:
Create a connection for each thread. Even if the thread calls the close method, it will not close. It just puts the connection back into the connec ...
Posted by jyhm on Fri, 01 May 2020 22:16:17 -0700
Note: this post is based on Basic query example of database (1)1. Query all f ﹣ name values corresponding to each s ﹣ ID in fruits table
#Compact in groups
mysql> select s_id,group_concat(f_name) as name from fruits group by s_id having count(f_name) > 1;
2. How many rows are counted for the same s ﹐ ID value?
mysql> select s_id,co ...
Posted by steven_84 on Fri, 01 May 2020 22:07:36 -0700
mysql container information
CONTAINER ID: 478bbac9137b
Currently, you use the MySQL container of docker to use mysql. As long as you run the container, you can use the local t ...
Posted by Randwulf on Fri, 01 May 2020 19:03:19 -0700
mysql's collation roughly means character sorting.
First, characters are inherently size-insensitive, so a rule of character order is required for character >, =, <operations.collation does this either by setting the character order of a table or by setting the character order of a field separately.A character ty ...
Posted by bailo81 on Fri, 01 May 2020 18:36:33 -0700
1. Log in with root
admin@lnxServer:~$ mysql -uroot -p123456
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 154
Server version: 5.6.19-0ubuntu0.14.04.1 (Ubuntu)
Copyright (c) 2000, 2014, Oracle and/or i ...
Posted by Shygirl on Fri, 01 May 2020 01:25:14 -0700
Recently, when dealing with a table splitting problem, we need to create a stored procedure for the program to automatically split tables. We need to ensure that all table structures, constraints, indexes, etc. are consistent. In addition, views, stored procedures, permissions, etc. are not considered temporarily.
In Mysql, the procedure of cre ...
Posted by DJH on Thu, 30 Apr 2020 21:46:48 -0700
In most applications, the group concat function is usually used for row column conversion. In fact, the group concat function also has a very important function, that is, sorting within groups.
Group ABCD concat full syntax:
Group concat ([distinct] field to connect [Order BY ASC/DESC sort field] [Separator 'Separator'])
1. Basic usage:
Posted by bsteimel on Thu, 30 Apr 2020 18:48:23 -0700
CentOS 6.5, MySQL multiple instances (in fact, the same principle applies to a single instance)
1, Problem description
[root@www ~]# /data/3308/mysql start
[root@www ~]# ps -A|grep mysql
Start mysql database, and there is no result by checking the process.
2, Problem solving
Check the mysql error log. Th ...
Posted by tmk4php on Thu, 30 Apr 2020 15:28:40 -0700