modelo-relacional

I am creating a system for selling products and I need that these products can have different prices according to their size ... el I created would this be possible? Follows the model: If anyone wants to import the template into your MySQL Workbench.

At the conceptual design level we can use the approach (relationship entity modeling (MER)) to describe the behavior of futur ... I just read the Chapter 7 Source: database systems 6th edition, authors: Elmasri, Ramez Navathe, Shamkant B. Year: 2011

What is the difference between associative entity and the Intermediate table of relationships N to N ? Is there any noticea ... epresented by a rectangle around the relationship. And N-to-N relationships don't. Relationship N to N Entity Associative

I was looking at the conceptual model diagrams, I saw some that contains the attributes and entities like this: And other ... ? If it is necessary to declare the attributes, what is done when a Entity has a huge amount of attributes, like 30 or more?

I have been learning about foreign keys and I am having difficulty understanding how useful they are. Its purpose would be to ... you give me a light? I spent the day trying to understand about it, I understood, but in the application I see nothing more.

Hello, I will develop a project for my computer technician course and I am having difficulty with an E. R. model. This is the ... ould look good with the ingresse.com (I don't know if I can put links here). I did one like this, but I think it's wrong:

I am modeling a database related to e-commerce and I am having a doubt in modeling the tables of categories and subcategories ... ch will be a subcategory. What are the advantages of doing a model with two tables or only one, as mentioned in the article?

I am developing my CBT and came across the following doubt in my MER(relationship entity model). I have a client entity that ... in ER? Type so I'm talking about: CLIENTE (nenhum,muitos) ---- PAGA ---- (nenhum,muitos) CLIENTE Would Look that way?

Context Consider the sentence below: States: Relationships that are the result of the combination of other relationships ... FCC - 2012-TRE-CE - Judicial Analyst-Systems Analysis discipline: database (it) - subjects: MER (relationship entity Model)

Explaining the context On the internet I found an example of a scheme described like this: Account (num-account, descr-a ... t, descr-account) and launch(numconta, NUM-lanc, data-lanc, value-lanc). Doubt Would the above example be normalized to 3FN?

this question already has answers here : ... ith foreign key. So what's the point of declaring a field as foreign key? I don't see any sense. Can anyone please explain?

this question already has an answer here : ... h of them are used and why, if possible with real examples. I accept indications of subjects for study, Thank you very much.

Hello, I am starting the study on conceptual modeling and entity relationship until I came across a doubt and so far I have n ... I did not see any similar example, so I wanted to know if it is so even or do you have another way to solve this scenario?

I need to make a simple system of registration of brands, but I would like the person who is registering a new brand to be lo ... odel. If I have something wrong with my template, can you let me know and help me put the Login table? Here is my Model:

I need to take all users with "Exceção " those of the function that contains id=2, is it possible? Can you fit a Where into ... sents the id of the function find(1) However I need to catch all users of all functions except the do id = 2 is possible?

In relational database, what is the difference between conceptual, logical and Physical Modeling? Could you give an example?

I have a table Livros and I know that specialization / generalization of books are Livros de Ficção, Livros de Drama and Livr ... e, I would have to program The Associated rules. Something is bothering me in both solutions! How do I resolve this impasse?

Hello, I am developing an application where there will be an option to add friends,it is very simple, it is not a social netw ... ria) - Deletes the record from the request table. But what would the types of relationship look like, from which to which?

What are the differences between relational databases and object-relational databases?

Good afternoon guys ! Is that okay? How the hell do I assign cardinality in a scheme like this ? I am extremely confused as I have never used sets before.. relationship can receive cardinality ? Thank you and have patience with my noobice pfvr