Erd

[Qamar]

while there are several advantages of using an ERD, can someone tell me if there are any disadvantages apart from the diagram being cluttered if a complex database is required ?

Thank you

 

[gemma-the-husky]

In any big system you will end up with many tables, and hundreds, maybe thousands of data elements, which need processing

Any system that helps you organise these successfully into the candidate tables, and thereby refine and finalise your design is worth considering.

I am not even sure what technical names all these systems have. They are surely just variants of the same thing anyway.

 

[Qamar]

thank you for your feedback. actually i have been doing some research on the net and the most common disadvantages that i found are:

Limited constraint representation
Limited relationship representation
No data manipulation language
Loss of information content

However, from the above points i only understood the 2nd point, so i was concerned if i am doing something wrong by using them.

Thank you

 

[gemma-the-husky]

I can understand the first. The ERD won't let you express the constraints in the links between two entities, or maybe constraints affecting certain attrributes.

I am sure experts in this and other methodologies will be able to add some comments

 

[Qamar]

Does anyone knows what these two mean exactly please?

No data manipulation language
Loss of information content

Thank you