IPv4 CIDR Chart
CIDR stands for Classless Inter-Domain Routing and is a method for allocating IP addresses as well as for IP routing.
It was introduced in 1993 by the …
Read Article →Technical Articles
In-depth guides, insights, and best practices for modern software engineering
Recursively Delete Files and Folders and all Contents using PHP
Below is a quick and easy way to recursively delete all files and folders in a given path using PHP.
function destroy_dir($dir) {
if (!is_dir($dir) …Product Update: ADD becomes Serengeti
As a product update; The “Autonomous Distributed Database”, otherwise known as simply ADD has been renamed to Serengeti.
The Serengeti is …
Read Article →SQL to Append all Fields if Shorter than a set Length
This came in very handy for me at one point because I needed to have a certain field in each row 14 characters long, but half of them were only 12 …
Read Article →Validate Email Address in Javascript
Need a quick client-side email validation? Below is a simple JavaScript regular expression to validate email addresses. …
Read Article →Remove hash from window.location in Javascript
E.g. URL:<br>http://example.com/?option=1&task=2&listing_id=36&layout=4&table=5#some_hash_value_here
So how would you get the …
Read Article →The Benefits and Dangers of Artificial Intelligence
Artificial Intelligence (AI) is usually defined as the science of making computers do things that require intelligence when done by humans. (Jack …
Read Article →The Decoded String at Index using Java
The Challenge
An encoded string S is given. To find and write the decoded string to a tape, the encoded string is read one character at a time and …
Timing Issues in Real-time systems
What are Real-time Systems?
If you look up the term “real-time” in a dictionary, it will tell you that it is the actual time during which …
Read Article →Find the Minimum Absolute Difference in BST using Java
The question
Given a binary search tree with non-negative values, find the minimum absolute difference between values of any two nodes.
Example: …
Read Article →Get the Second Highest Salary in MySQL
The problem
Write a SQL query to get the second highest salary from the Employee table.
+----+--------+ | Id | Salary | +----+--------+ | 1 | 100 …Read Article →
Find Maximum Subarrays using Java
The problem
Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum. …
Finding Number Complements using Java
The problem
Given a positive integer num, output its complement number. The complement strategy is to flip the bits of its binary representation. …
Forensic Analysis on Linux (Unix)
Operating Systems come in a few competing choices, of which the major players are Apple’s MacOS, Microsoft’s Windows and then the various …
Read Article →Self Dividing Numbers using Python
Introduction
A self-dividing number is a number that is divisible by every digit it contains.
For example, 128 is a self-dividing number because 128 % …
RuntimeError: thread.__init__() not called (Python)
Today I got a really dumb error from Python.
RuntimeError: thread.init() not called
But luckily it’s really easy to fix!
Below is the code …
Read Article →All About Distributed Databases
A database “is a structured collection of data. Card indices, printed catalogues of archaeological artefacts and telephone directories are all …
Read Article →Network systems security risks
Networking has played a vital part in the transfer of information as well as the accessibility of information that was never available to previous …
Read Article →Communications and The Software Development Process
Software Engineering or the Software Development Process is broken down into the following phases.
- Requirements
- Design
- Implementation
- Verification …
Get the total size of all the files in a directory
It’s amazing how many times I’ve need to find out the total size of all the files in a directory on one of our servers.
I have grown to …
Read Article →Structured and Object-Oriented Programming
Software development has really come a long way over the past few decades.
Programming used to always be about doing things in a very procedural way, …
Read Article →Moving a MySQL Database without downtime
At Statvoo Analytics we found ourselves in the position where we needed to move our master MySQL database without ANY downtime and for anyone …
Read Article →How to use Google Analytics in AngularJS
It seems to be quite a popular question with not as many answers to hold the weight.
Google Analytics has always been more of a pageviews type …
Read Article →Converting from Legacy to Client-Server or Distributed Systems
What is a legacy system?
A legacy system is a computing system that has been around for a very long period of time, tends to be difficult to maintain, …
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