LANP No Network Tower Blog

LAMP="Linux Apache Mysql PHP/Python" Linux is often referred to as a system, and there is no explicit version, such as CentOS/Ubuntu/Debian, which can be used as a server system. Apache is the engine of Web parsing, which is used to process Web source files into browser convertible page files. MySQL database, MySQL is a relational database ...

Posted by pmzq on Mon, 14 Oct 2019 11:11:53 +0200

Programming Literacy Day004

I. JavaScript Programming Problem Enter a year (to be verified) on the page to determine whether it is a leap year (year divisible by 4, but not by 100; leap year divisible by 400), and display the corresponding prompt information on the page. (1) Code <!doctype html> <html> <head&g ...

Posted by The_Anomaly on Sat, 12 Oct 2019 20:32:37 +0200

MySQL Execution Plan -- Reasonable Utilization of Implicit Business Logic

Problem description An SQL was encountered in the optimization process: SELECT SUM(user_value) FROM user_log WHERE del_flag = 0 AND product_id = 2324 AND user_type = 1; Its implementation plan is as follows: *************************** 1. row *************************** id: 1 select_type: SIMPLE table: use ...

Posted by tensitY on Fri, 11 Oct 2019 16:15:26 +0200

Introduction of data types of java prometheus

I. Introduction Prometheus saves all collected sample data in a time-series manner in a memory database and on a hard disk at regular intervals. Each sample in time series consists of three parts. Indicators (metric): metric name and labelsets describing the characteristics of current samples, such as < metric name > {label name >= ...

Posted by cleartango on Fri, 11 Oct 2019 10:00:41 +0200

Backup using rsync tools

rsync is a remote and fast incremental backup tool that supports local, ssh and rsync host synchronization.rsync is one of the basic components of the default Linux/Unix system installation, so we don't need to install it manually. [root@mysql /]# rpm -q rsync rsync-3.0.9-17.el7.x86_64 rsync programs do not have configuration files, so we need ...

Posted by webwiese on Mon, 07 Oct 2019 00:54:11 +0200

Spring configures multiple data sources

Spring configures multiple data sources configuration file The first configuration class The second configuration class Catalog display Explanatory notes configuration file spring: datasource: master: driver-class-name: com.mysql.jdbc.Driver url: jdbc:mysql: username: ...

Posted by hightechredneck on Sun, 06 Oct 2019 22:39:39 +0200

python's Django framework (use of APP and ORM)

12.3 APP 12.31 Create APP A Django project can be divided into many APP s to isolate code from different functional modules. Create an APP from the command line: python3 manage.py startapp app01 Create an APP, remember to tell Django the name of the app, add in settings.py: INSTALLED_APPS = [ 'django.contrib.admin', 'djan ...

Posted by CBaZ on Sat, 05 Oct 2019 10:10:56 +0200

JDBC Connection Pool Technology and Druid

JDBC Connection Pool Technology and Druid Because database connection is a kind of resource, it must be created before use, and this process has time and space overhead. If the connection is created every time when database access is executed, and the connection is closed after use, this process is ...

Posted by D1proball on Sat, 05 Oct 2019 06:22:53 +0200

hplsql installation and common problems

1.x version of hive does not provide the function of similar stored procedure. When using Hive for data development, it usually encapsulates a paragraph of HQL statements in Shell or other scripts, and then calls them by command line to complete the statistical analysis of a business or a report. The go ...

Posted by facets on Mon, 30 Sep 2019 22:36:40 +0200

Construction of python django+bootstrap4+mysql intelligent transportation system

Before, I did a training project, but I haven't shown how to do it. Now let me explain how to use Django + bootstrap 4 + mysql to implement this intelligent transportation system. The bootstrap 4 framework and mysql database are used here.   First: Contents of Software Projects 1. Brief introduction of training projects Intelligent Transpor ...

Posted by 14zero on Mon, 30 Sep 2019 22:00:46 +0200