SEARCH KEYWORD -- DROP TABLE



  How Query Optimizer Works in RDBMS

In a previous post, we discussed how the various relational operators are implemented in relational database systems. If you have read that post, you probably still remember that there are a few alternative implementations for every operator. Thus, how should RDBMS determine which algorithm (or implementation) to use? Obviously, to optimize the performance for any query, RDBMS has to select the correct the algorithm based on the query. It would not be desirable to always use the same algori...

   DATABASE,DATABASE DESIGN,DATABASE OPTIMIZATION     2019-04-20 07:26:32

  OT Railway System Development: How to Use PLC to Implement Land Based Railway Track Fixed Block Sign

Figure-00: Railway fixed block signaling system over view diagram, version v1.3 (2024) Project Design Purpose: This project aims to use Programmable Logic Controllers (PLC) with train detection sensors and train control signals to develop an automated OT system for railway track fixed block signaling control. The system will include a digital equivalent simulation to explain the logic of the track fixed block Automatic Train Control (ATC) mechanism for demonstration and training purposes. In th...

       2024-07-27 04:08:41

  When and How to Use the Go Channel

Go’s concise structure and powerful native library enable us to hit the ground running easily. It is more efficient than Java or Python when implementing the same functions, especially its concurrent programming, which is very handy and widely admired due to its goroutine and channel. goroutine and channel has much to dig into, and let’s start with channel, which I used to consider narrowly as a message queue to transfer data between gorouti...

   GOLANG,CONTEXT,CHANNEL     2022-09-17 23:06:36

  As A Hottest Job Ever, What Should You Know As A Front End Web Developer?

The front end web developers are the openers for the visitors to visit the web page. It is also known as the client-side development, works predominantly with HTML, CSS, and Javascript. The tools and techniques are the important players of the front end web development. The developer must be aware of the updation of web technologies.The scope is evergreen with this technology as every company or business needs a website to showcase their profile. There are many objectives must be measured while ...

   FRONT END DEVELOPER,WEB DEVELOPERS,SOFTWARE DEVELOPERS,TOP SOFTWARE COMPANIES     2019-08-12 05:36:28

  People Detection Radar [IoT] : Build a Raspberry PI Xandar Kardian IoT People Count Radar

Program Design Purpose: People detection sensors and radars are utilized in various applications across multiple fields such as security and surveillance, healthcare, building automation, smart cities, transportation and autonomous manufacturing systems. This project aims to develop a prototype IoT device for an indoor people counting using the Xandar Kardian people detection radar and a Raspberry Pi. The device will be network-ready and easily integrated with other systems. The Python-based I...

       2024-07-21 08:19:57

  How big company CEOs spend their time in work

As a company's steer holder, the CEO or founder takes plenty of pressure ordinary people even cannot imagine. They usually need to deal with different aspects of daily operation of a company including technology, business, marketing, public relationship etc. Lots of meetings, negotiations and presentations are waiting for them every day. Hence time is a precious resource for them. Let's take a look at how these CEOs spend their time in their work. 1. Apple CEO Tim Cook Gets up at 3:45 am ...

   CEO,STEVE JOBS,TIM COOK,ELON MUSK,JACK MA,MARK ZUCKERBERG,PONY MA     2016-08-13 13:29:00

  Python and PLC Communication

This article provides detailed steps on how to use Python to communicate with Schneider M221 and Siemens S7-1200 PLCs via Ethernet. Additionally, we offer a packaged Python PLC client library, enabling you to easily build your own SCADA control programs, such as Human-Machine Interfaces (HMI). The system overview is shown below: To check the project detail please refer to Python Physical PLC Communication Clients # Created: 2024/06/29 # Version: v0.1.3 # Copyright: Copyright (c) 2024 ...

   PYTHON,PLC,COMMUNICATION     2024-06-30 02:21:17

  CASSANDRA data model

Cassandra is an open source distributed database, it combines dynamic key/value and column oriented feature of Bigtable. Features of Cassandra are: Flexible schema, no need to design schema first, it's very convenient to add or delete strings Support range search on keys High usability, extensible. The single node error will not affect the cluster. We can think Cassandra's data model as a 4 or 5 dimensional Hash. COLUMN Columns is the smallest data unit in Cassandra, it is a 3 dimensional data...

   Cassandra,database,sort     2013-06-08 22:07:40

  How to Develop a Successful SEO Strategy for Your Startup

SEO is usually viewed as under-the-table formula manipulations and trickery, once actually it’s simply a series of core steps and actions you wish to require, to create your web site rank higher. An economical SEO strategy may be countermined to the subsequent three parts, that create the entire issue look less daunting in spite of everything.   Step 1: On-site Optimization On-site optimization strategy consists of these subsequent elements: Your Content Website Structure Layout of ...

   SEO,MARKETING     2016-03-18 15:33:37

  Use DTrace to diagnose gdb issues

A few days ago, I installed the newest 64-bit gdb program (version 7.7.1) on Solaris 10 (X86_64 platform) to debug programs. After playing with the gdb a day, I found 2 issues about gdb:(1) The "set follow-fork-mode child" command doesn't take effect. By default, after the parent process forks the child process, the gdb will track the parent process, so this command can make gdb begin to follow the child process. But this command works OK on Linux.(2) The gdb can't parse the 32-bit application c...

   DTrace, debug, gdb, UNIX     2014-06-28 05:11:20