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Docker packages nodejs project and database

To read this article, you must know the basic docker. This article only provides ideas and part of the code, not responsible for teaching All orders must be handled carefully! look before you leap command Stop all running containers docker stop $(docker ps -a -q) Delete all containers docker rm $(docker ps -a -q) Using docker compose to start the container docker-compose up -d Use docker compose...

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Using SQL Server database for python3 connection (linux version)

statement My sample environment: System version: CentOS 7.1 Database version: SQL Server2012 python version: Python 3.6.3 Connect to database tools: pyodbc, freetds If you use Django to connect to the SQL Server database, please refer to the blog "Django 2.1 connect to use SQL Server(linux version)", which is different from that, Django 2.1 uses Microsoft ODBC Driver 11 for linux...

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Easy database operations with Groovy and Gradle

Groovy: Stylish Language Not everyone thinks the Java programming language is sexy.However, from the most conservative to the most bizarre start-ups, Java virtual machines are the dominant force everywhere.Today, there are many alternative languages that can be compiled as Java byte codes.There are multiple implementations of Python, Ruby, and JavaScript based on JVM.There are new languages, such...

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4. Principle and use of spark--sparkSQL

[TOC] 1. Overview of spark SQL 1.1 What is spark SQL Spark SQL is a module Spark uses to process structured data. It provides a programming abstraction called DataFrame and functions as a distributed SQL query engine.Similar to what hive does. Features of 1.2 spark SQL 1. Easy to integrate: When you installed Spark, it was already integrated.No separate installation is required.2. Unified data...

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New feature of Oracle 12c: online conversion of non partitioned tables to partitioned tables

concept Nonpartitioned tables can be converted to partitioned tables online. Indexes are maintained as part of this operation and can be partitioned as well. The conversion has no impact on the ongoing DML operations. You can convert non partitioned tables to online partitioned tables. Indexes are maintained as part of the operation and can also be partitioned. The...

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[PHP] single example of the connection between PHP PDO and mysql to prevent timeout

This database class mainly deals with creating database objects in the single instance mode. If there are two long time intervals to execute sql operations, the problem of connection failure will occur when processing again. A cache array is used to store pdo objects and time stamps, and the time between the two executions is compared. If the interval is more than 10 seconds, the connection will...

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JDBC programming - get Connection and common problems

Connect to Oracle using JDBC Implementation ideas: Use a file named oracle.properties, which contains the Oracle URL, User, Password and driver classes. Through the input stream of ClassLoader, the input stream contains the Oracle connection initialization parameters of the input program. The input stream is loaded in the Properties load. Get the file information through getProperty(String...

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Mybatis source code analysis - Mapper creation and Spring management

Mybatis source code analysis - Mapper creation and Spring management When we analyze, we first guess the implementation mode and then compare the source code implementation mode of mybatis mapper creation Because mybatis can be used independently of spring, the bean creation of mapper is completed by mybatis According to different mapper s, the methods are corresponding to the names of...

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SQL function calculates 95 values of traffic

I use the Solarwindows system, and some of the content is written in conjunction with the Solarwindows system.The final landing is also automatically reported and mailed through the system's Report Timer. However, the calculation method is obtained by defining the SQL function and then using the SQL query, which is generic. 95th calculation method Search the official Solarwindows website for...