Thursday, July 29, 2004

Organization & Tables

I believe you all have practiced the family table example. Before we get into more defining authorities in data, we shall see why we need data modelling.

Let us try one thing first, take a sheet of paper and write all the family members of your family with name, age, sex, occupation, role in family. Now try writing the names of family members of your friends.

Now try to take the relevant information of your mother - what is her age & occupation. I believe you will find it difficult to read out the information - but you will do fine. Assume you have written names of all your friends, immediate relatives, and information about their families too (take some 100 pages of data). Will it be easy to fish out some specific information from it. No, not definitely.

That's where the power of organization comes in. If you organize such raw data, then you can easily collect information. One sample is organize the data by drawing a table matrix to represent the data in separate rows which are relevant with families. The above statement is nothing but representing the data in table format. Now the fishing out of information becomes lot more easier - but not as easy as such (U have to still search 100 pages).

Our brain itself has information stored in a manner similar to this. When you want to remember the name of your friend's mother, it actually looks up into all the relevant persons you know along with your friend - narrows it down to his/her mother and gives you the result. Brain being so powerful in search is very efficient in getting back things from your memory. But in physical case, you need a powerful tool to store data and a easy search to get your data as information. This tool is your Database & Query. Sounds very familiar right.

Similar to our question to our brain - the query to a database needs to be in a specific language - the one the database understands. That language is the 'sql'. The 'sql' has a simple set of grammar which you should follow, such that it is valid 'sql' statement. Simply to say 'sql' is the language you speak with your database (storage). You can say the database how to create the tables with what columns etc., - it takes care of organizing and storing the data in the computer.

PS: Difference between Data & Information - Data is nothing but raw data you get. Just a name of a person (some YYY/ZZZ data). Information is a processed data which specifies the Name is of this person working in this field etc. You always store raw data in Databases and use your application to process this raw data to create information - to be used. Simply, Information is nothing but meaningful data.

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