Before Class Question: May 29, 2012

Please spend 100 seconds to reflect on what you have learned in ER Diagram, and Database Schemas.

What is the most important thing you learned in the first week?

19 Responses to “Before Class Question: May 29, 2012”

  • The most important concept I learned was the ER Diagram. More specifically, I learned the ER Diagram is the crucial first step in constructing a database, it is the “blue print” of the database. It allows the creator to map out the data flow of the database in order to construct the fastest and most cost efficient relationships between entities. I learned there are three parts of an ER Diagram: An entity, a relationship and an attribute. An entity is a uniquely identifiable object. A relationship provides/creates a link between two entities and is usually a command in verb form. Lastly, an attribute is a characteristic of an entity or relationshi

  • The most important thing I learned in this first week was how to construct an ER Diagram. First you have to identify the problem, and then identify your entities, attributes and the relationships formed between entities. Entities are modeled by rectangles, attributes by ovals, and relationships by diamonds. I understood this concept quite easily, but cardinality gave me a bit more of a challenge. I really have to read the problem closely in order to decipher exactly which type of relationship is present between entities. After grasping all this, it was much easier for me to convert all these shapes to a table format. With tables it is crucial to remember that with many to many relationships, a new associated table needs to be drawn.

    • Justin, you and Sebastian expressed very valid take aways from the first week. I too have learned the vital importance of an ER diagram and the significance of creating a table with the right relationship. With practice and studying these ERD’s will become easier for you, the fact that you were able to take away the importance of it is a great start.

  • The first week I learned about modeling a database and how ER diagrams work. It is important to start with a problem statement, gather documentation, and conduct interviews.To construct the ER diagram you need an Entity which is a uniquely identifiable thing. Secondly you need the relationship which describes how the two entities relate to one another, and lastly you need an the attribute which is a characteristic of an entity or relationship. After you have understood the data map you can implement a database schema which is a map of the tables and fields in the database.This is a way of organizing data to minimize redundancy.

  • In my first week of Data Analytics, I have found that constructing the ER diagrams are the most important things we have learned in class so far. As stated in class, ER diagrams, are one of the more important building blocks when talking about Data Analytics. The key two keys to ER diagrams are being able to identify the entities, attributes, and relationships. The next biggest is understanding cardinality, which is more challenging, but with practice, makes reading the diagrams much easier.

  • As everyone has said, the identification of entities, attributes, relationships, and cardinality has been the most important thing that I have learned in the first week of classes. I think I’m getting the hang of these. Schema are pretty straightforward; entity, attribute, and relationship are more clearly identifiable.

  • During the first week of classes, the most important thing that I have taken away is the logic behind building a database, in general.

    Through learning about the ER Diagrams and the Schemas, I feel as though I am beginning to appreciate the actual mechanics that support a database. This helps me set up a foundation for understanding and ultimately using a database to create business solutions with a higher degree of versatility/resourcefulness.

  • The most important thing I have taken away from the first week of class is constructing an ER diagram. I’ve never broken down data before, analyzing each entity, their attributes, and how they are related. After last weeks classes and our first assignment, i now have a new perspective of what data really is!

  • The most important thing I learned this week was about the ER diagram and how to construct them. Its important to construct the diagram according to entities and their atributes, etc. Understanding the cardinality can be difficult but with practice it comes easily.

  • The most important thing is to know how to transform a real problem into a ERD or a database. Also, ot is amazing how any problem can be solved using these techniques.

  • Similar to everyone else, I also believe that the most important takeaway from the first week was the ERD. In my opinion, it was the most difficult topic of the first week to understand as well. By learning how to map an ERD, I’m beginning to understand how data fits together, and the necessity of creating an entity in order to do so. While the ERD and the database schema are there to complement each other, I found the schema to be far more aesthetically pleasing. Unlike the ERD which is scattered all over the page, the schema is packed neatly into rows and columns.

  • ERD is made up of Entities, relationships, and attributes. It is easier to make corrections on ERD rather than the schema.

  • The most important point of ER Diagram is that it can simplify and organize data very efficiently and effectively, since you can reduce redundancy and express quite complex data in a simple manner.

  • I’d have to say the most important takeaway from the first week of this course would have to be constucting an ER Diagram. I feel that it will be necessary to know and understand how to construct one in this course. Not only do the ER Diagrams make everything flow together easier but they save a great deal of time as well.

  • I learned that ER diagrams are the first conceptual step in creating a database. These diagrams take relationships entities and attributes into account in order to express the data coming into the database. ER Diagrams in a way give the data context and structure for a specific buisiness fit.

  • I learned that a database contains a bunch of information and within the database are different tables that are related to each other. Each tables is connected by a primary key. An Er diagram has an entity ( unique thing), attribute (characteristic of an entity or relationship) and a relationship that connects entities. Each entity has a primary key.

  • I learned that ER diagrams help form a logical string of how databases are created; once the diagrams are complete, the schemas show the relationships in a easier-to-read format as data and then used for analytics.

    The most important thing I learned in the first week is how to make connections with data when problem solving databases. I’m sure there’s a lot more to learn but I believe the fundamentals of databases, whether transactional or analytical, starts with ERDs and Schemas.

  • ERD is the model of a database. It is the first and important part of building a database. Without it, a database will simply mean or do nothing. When building a database that will hold thousands of data, it is very important that a model works and is doing what it is supposed to do. The ERD describes what a database should contain and how data are related to one another. Before modeling, there is an important step to do: “Start with a problem statement”. If we don’t know what the problem is, it will be hard to find a proper solution for it. An ERD has three main components: A entity which is unique, a relationship describes how two entities are related to one another and attributes which is the characteristic of an entity.

  • The ER diagram as useful for visualizing how the information is related to the entities. In this diagram you will have entities, relationsihps, and attributes. The ER diagram is a visual demonstration of how tables contain fields, and tables together are schemas.

    Additonally learning about primary keys, and associated tables were important in figuring out how to relate two tables that are not directly related.