Step by step blog creation tutorials using PHP & MySQL: Part-3

E-R Diagram Design:

Hello everyone, today I want to start our tutorials with some important discussion. A visitor asked me that, I am learning PHP but I don’t completed all PHP essential tutorials. Am I capable of reading PHP blog tutorials. I say that it is very tough to understand some concepts before learning PHP basic concept. So I say that at first try to learn PHP basic tutorial then try our blog creation tutorials.    

So now turn our main PHP blog creation tutorials. Today I show you how to draw the entity relationship diagram for PHP blog. So at first you need to know what is E-R diagram. Entity Relationship diagram is a diagram that show you the relation between the entity. E-R diagram helps us to design our blog database. It is a part of database design.
Think that a user make a comment in our blog. User and Comments is two entity of our PHP blog. So that, there is a relation between user and comments entity because user make comments. So the diagram is 

We use a arrow sign to the comment box because user make comment. User comment is depenedent on user but user is not dependent on comment. For this reason, we use signle arrow. If the relation is two way then we use two way arrow. We just draw our concept now we make relation between those fields by following way.

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