Showing posts with the label SQL

Relational Databases

By McDonald, T.   |  Date 5th of November 2020 Why use a database? Databases are a great way to store and retrieve data.   Since they are so widely used in computing, knowing how to use them is a must have skill in this industry.   For instance, many websites use databases to store product details.   One of the main benefits to databases is allows data to be organised, manipulated and retrieved rather than just storing it making it a very powerful tool.      Tables and keys First let’s look at the parts of the table  Customer_Table customer_id name address phone 1 Tony McDonald Some place 0788454567 2 A man 17 somewhere else 0793453459 3 A woman 45 who knows 0712311180   All relational databases have columns and rows.   Columns are vertical, so phone is the label of a column containing phone numb

Databases: SQL and NoSQL

  By   McDonald, T.    | Date 20th of November 2020 What is a database? A database can be anything that stores collection of information and is often abbreviated to DB. A relational database stores information that is related in some way. For example, a shopping list is a relational database since it is a list of related information. Other examples include: Phone book. List of twitter users. Your families favourite foods. Now you have an idea of what a database is we can talk about where to store it. In the examples above, the phone book is a list of numbers and related information that can be stored in a book. The shopping list is stored on paper. We can also store these databases on a computer. Notably, the computer can be in your office or be a dedicated computer in a server room or even stored in a virtual machine in the cloud, which uses dedicated computers. Keeping it simple for now we can just think of a computer hosting the database. Now we have a place to store the d

Nuclear Test Map For 1969 to 2017

By T. McDonald | 29/07/19 | Updated 07/10/19 Did you know that nuclear tests can be felt on the Richter scale? This investigation maps the nuclear tests registering 5.5 or greater on the Richter scale from 1969 to 2017. (Click on the markers to find out more about that test). At first it may look as if there are not many tests, but if you zoom in on one of the clusters, you will see many more markers. During the investigation it was discovered that the cause 'explosion' was actually four more nuclear explosions. Twelve test sites were discovered with six consisting of many tests, and six with less than ten occurrences. North Korea with just one test was the last nuclear explosion detected in the dataset. The average magnitude showed no real difference with nuclear a explosion was 5.86 and earthquakes at 5.87.  Furthermore, the biggest nuclear explosion was in 1973 and took place at Novaya Zemlya, Russia.  Further investigation revealed little difference between