DRAG DROP
Note: This question is part of a series of questions that use the same scenario. For your convenience, the scenario is repeated in each question. Each question presents a different goal and answer choices, but the text of the scenario is exactly the same in each question in the series.
You have a database named Sales that contains the following database tables. Customer, Order, and Products.
The Products table and the order table shown in the following diagram.
The Customer table includes a column that stores the date for the last order that the customer placed. You plan to create a table named Leads. The Leads table is expected to contain approximately 20,000 records. Storage requirements for the Leads table must be minimized.
You need to begin to modify the table design to adhere to third normal form.
Which column should you remove for each table? To answer? drag the appropriate column names to the correct locations. Each column name may be used once, more than once, or not at all. You may need to drag the split bar between panes or scroll to view content.
Answer: 
Explanation:
In the Products table the SupplierName is dependant on the SupplierID, not on the ProductID. In the Orders table the ProductName is dependant on the ProductID, not on the OrderID.
Note:
A table is in third normal form when the following conditions are met:
– It is in second normal form.
– All nonprimary fields are dependent on the primary key.
Second normal form states that it should meet all the rules for First 1Normnal Form and there must be no partial dependences of any of the columns on the primary key.
First normal form (1NF) sets the very basic rules for an organized database:
– Define the data items required, because they become the columns in a table. Place related data items in a table.
– Ensure that there are no repeating groups ofdata.
– Ensure that there is a primary key.
References: https://www.tutorialspoint.com/sql/third-normal-form.htm
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