week 1 questions

Why do relational databases use both primary keys and foreign keys?

to create relationships between entities

Which of the following describes structured data?

1. a defined length, type, and format 2. includes numbers, dates, or strings such as Customer Address 3. is typically stored in a relational database all of these

A primary key for a database table (entity) is used to distinguish each record in a table so that individual records:

2. can be manipulated; such as to update a field value in a specific record 2. can be accessed; such as to view all data attributes for a specific customer 3. can't be accessed as relational databases don't generally work with primary keys 4. 2 of the above are correct- correct answer

What is the primary difference between an entity and an attribute?

An entity is a table that stores information about people, places, or events, whereas an attribute is a column or specific field of the data elements associated with an entity.

A transaction processing system (TPS) is the basic business system that assists operational level analysts when making data driven decisions. Which of the below is not an example of a TPS?

Comfort Dental 's x-ray pictures

What is the role of a foreign key?

It is a primary key of one table that appears as an attribute in another table and acts to provide a logical relationship between the two tables.

Suppose you have a database table named INVENTORY that contains all the products a company sells. The table contains the inventory item # (primary key), item description, and the sales price for each inventory item. The database also contains a table named SALES that contains data about every point-of-sale made (at a brick and mortar store) and each inventory item # sold on that sale. as a foreign key. I want a Sales-Item report that lists all Sales, each and every inventory item # sold on the sale, and the description for each item on each Sale. Which of the following are true - select all that are correct.

The report will require 2 tables to be linked together The 2 tables will be linked together with the inventory item # field

what is a primary key?

a field (or group of fields) that uniquely identifies a given record in a table

what is a foreign key?

a primary key of one table that appears as an attribute in another table and acts to provide a relationship among the two tables

What of the following are the characteristics of unstructured data?

all of these

In the relational database model, what is a person, place, thing, transaction, or event about which information is stored?

entity

What is a tool that retrieves information and helps end users graphically design the answer to a question?

query-by-example tool

Which of the following is used to write lines of code to answer questions against a database

structured query language