lab 3.2

1.Question - Databases surround us on the web and everyday life. Now that you have a cleareridea of what database systems do, find two examples of web sites that you believe
are likely to use databases and discuss what kinds of data they might be storing, asin the example answer.Amazon.com stores data about products, availability, 
customers, customerreviews, advertisements, etc.
	
ebay.com- stores data about products, advertisements
movies.com- stores data about upcoming movies, movies out, reviews




2. Question - Identify relationships. Suppose you are creating a database to help a universitykeep track of its course offerings. You might have the following entities in yourdatabase, 
since they are distinct items in real life that are related to each other inimportant ways: course, classroom, professor, and department. In the spacebelow, draw an ER diagram with a box for each of 
these four entities and arrowsbetween the boxes labeled with the relationships they denote. (Don’t worry aboutwhat fields each of these entities should have for now.) See the example 
ERdiagram in your textbook and in Part 1 of this lab.

If a university wanted to keept track of course offerings, it could first order the classes by department. Then in every department,
the professors could be listed, and then what type of course the professor teaches. Finally, the location of the classroom could be stored.




3.Question - Identify many-to-one relationships. For each of the relationships you diagrammedabove, which ones are many-to-one? 
Which ones are many-to-many? Indicatethe relationships by writing 1 or ? at each end of the relationship arrows. If youare not sure about whether a 
relationship is one-to-many or many-to-many,explain why.
	
It is when one thing can be tied to several different things
	
A director can be tied to 7 different movies




4. Question - Identify entities. Suppose you are creating a database to keep track of a radio
station’s record collection. What are some of the entities your database might
include?

To keep track of a radio station's record collection, a database would contain artist, track name, release date, date last played, number of plays, 
and number of requests if offered.




5. Question - Query results and tables look very similar—like a set of tuples. How are query
results and tables different, however?
	
Query results can be arranged however you would like them to be,does not have set limitations applied A query 
orders certain information or desired information instead of listing every item.