Existential Duality - How Do Databases Work?
Apple Inc has filed a patent for a new technology called ‘transparent texting’. Those who text while walking can have a safer experience with this. The rear camera of the smart phone will play the live video of what is in front of the user. So she can see the path she is walking through with text over laying on it. This will prevent stumbling over objects in her path. This feature could be activated with just the press of a transparency button. But, I do not know if I can adapt, to concentrating on text popping on a live background screen and at the same time understand that that’s a stumbling block on the background, easily.
Now, here are the answers to my question in the previous article.
Here we have the table of an individual’s shopping details which we will call Shop_Det from now on.
Date | Shop_Name | Amount |
---|---|---|
01/01/2014 | VBJ Diamonds | 50,000 |
06/01/2014 | Kovai Fruits | 750 |
10/01/2014 | Nilgiris | 725 |
13/01/2014 | Kovai Fruits | 500 |
21/01/2014 | Max | 800 |
23/01/2014 | Kovai Fruits | 100 |
25/01/2014 | Baskin Robbins | 250 |
The data in this table is arranged in the form of rows and columns. In relational database terms the row is called a tuple and the column is an attribute. Here we have 7 tuples and 3 attributes namely ‘DATE, SHOP_NAME ,AMOUNT ’. So a relation is described as a table. A relation is a set of tuples with the same attribute. In this table each tuple talks about a particular well defined act called shopping where data about the act is described in each tuple. This relational model was first defined by Codd. He clearly defined a set of 12 rules that say what a Relational DataBase Management System( RDBMS) is.
So, whenever we make a transaction by swiping a card, data gets updated in the server’s database- in a similar table of this kind, which may not be this simple. Then an alert message reaches your mobile about the swipe; Of course, if your details of personal contact information remains up to date.
But what then is a database? Does data get arranged (only) in a chronological order like this automatically? Let’s learn that next.
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