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Editor's Column - Traditional DBMS

Editor's column
There were days when Rooms-sized processors used for processing data. IT boomed up at the start of 21st Century and so many innumerable inventions made Computer world and few among them are still up in the markets for thier better implemented programming Alogrithms which couples with computer hardware and software ( OS ).

Textpads or notepads were the repository of data and programmers had to be Experts to do data manipulation. In other words, Programmers had to use thier own logic to do insert , delete, update in data source.

For instance,

Consider the following:

file1.txt:
1 I am line number 1
2 I am line number 2
3 I am line number 3
4 I am line number 4
5 I am line number 5
6 I am line number 6
7 I am line number 7
8 I am line number 8
9 I am line number 9
10 I am line number 10


To programmatically delete 8 th record , developer had to use the following logic with OLD file handling methods in 3rd generation language.

1. Open file1.txt, and a temporary file temp_f.txt
2. Read lines one by one
3. Match the 8th line records
4. If matches, Dont write in file temp_f.txt
5. If match not found, write record in temp_f.txt
6. Repeat step 2,3,4,5 until the file1.txt reaches it end of line
7. Close file1.txt and delete file1.txt
8. Now rename the file temp_f.txt to file1.txt

Applies same for other DML operations!

User would never know file1.txt has just been removed of only 8 th records, but what actually happens is the file is completely read and except for one record everything is written into an another file and renamed to source.

As we are in 'RAPID-Technolgoical-Environment', we even ignore to read so much and look for what is intended.

Thanks to RDBMS which now makes everyone's task easy.

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