Chapter 5 of "Introduction to Flask": learning Flask Sqlalchemy is enough. Don't write too many
According to my personal understanding, database is a tool to store data and the direct relationship between data and data. No matter the complexity or size of the data it stores, it has no ess ...
Posted by parse-error on Sun, 14 Jun 2020 05:53:41 +0200
1, Why open slow query
Most of the reasons for the poor query performance are the large amount of data. To start the slow query of mysql and record the SQL statements that take a long time to query in the log is conducive to our better position and optimization.
2, Several common reasons for the ...
Posted by bg on Sun, 14 Jun 2020 05:47:10 +0200
<!--Add to mysql and mybatis rely on-->
Posted by Jragon on Sat, 13 Jun 2020 20:59:15 +0200
MySQL database backup can be divided into logical backup and physical backup. The logical backup tools are mysqldump and the physical backup tools are xtrabackup. The two backup methods have their own advantages and disadvantages
Support hot backup and incremental backup, requ ...
Posted by Gath on Fri, 12 Jun 2020 11:30:10 +0200
[Summary] For mysql primary and standby instances, seconds_behind_master is an important parameter to measure the delay between master and slave.Seconds_can be obtained by executing "show slave status;" on slaveBehind_The value of master.
For mysql primary and standby instances, seconds_behind_master is an impor ...
Posted by heldenbrau on Fri, 12 Jun 2020 06:20:43 +0200
With the wide application of NOSQL database, the extensible storage mode also has a good support in relational database. A new data type, JSON, has been added in MySQL 5.7
JSON data type meaning
In fact, without the support of JSON data type, we can save the data in this format by varchar type or text type, but why do we need to specifica ...
Posted by poppy on Wed, 10 Jun 2020 08:47:33 +0200
First of all, thank you for this little sister's video: Bili bilibili - very poor female programmer
List structure attached:
1, Development preparation
Node installation and configuration
MySQL installation and configuration
Database visualization tools: Navcat
Interface t ...
Posted by ukspudnie on Tue, 09 Jun 2020 07:08:23 +0200
Cacti is a software implemented in php language. Its main function is to obtain data through snmp service, then use rrdtool to store and update data. When users need to view data, use rrdtool to generate charts and present them to users. So the key of cacti is snmp and rrdtool. snmp ...
Posted by mem0ri on Tue, 09 Jun 2020 04:54:13 +0200
Oneinstack basic use
1. Features of Oneinstack:
2. Oneinstack open source software version
3. Deployment and installation of oneinstall
3.1 download oneinstall
3.2 decompression and installation
3.3 operation install.sh
Official website explanation chart:
3.4 installation process diagram ...
Posted by linda thomas on Sun, 07 Jun 2020 08:30:41 +0200
1.1 problem description
. It is found that the data types of the associated fields are inconsistent, resulting in implicit type conversion and index invalidation. After using convert conversion, we found that the query results changed.
Posted by dabbott on Fri, 05 Jun 2020 06:09:46 +0200