USING MYSQL WORKBENCH

BookStore_Maged Books has become the exclusive distributor for a number of books. The company now needs to assign sales representatives to retail bookstores to handle the new distribution duties.

For these assignments, create new tables to support the following:

1. Modify the following SQL command so that the Rep_ID column is the PRIMARY KEY for the table and the default value of Y is assigned to the Comm column. (The Comm column indicates whether the sales representative earns commission.)

1.

CREATE TABLE store_reps

(rep_ID int(5),

last VARCHAR(15),

first VARCHAR(10),

comm CHAR(1));

2.

Change the STORE_REPS table so that NULL values can’t be entered in the name columns (First and Last).



Answer

3.

Change the STORE_REPS table so that only a Y or N can be entered in the Comm column.



4.

Add a column named Base_salary with a datatype of decimal(7,2) to the STORE_REPS table. Ensure that the amount entered is above zero.



5.

Create a table named BOOK_STORES to include the columns listed in the following chart.

Column Name Datatype Constraint Comments

Store_ID int(8) PRIMARY KEY column

Name VARCHAR(30) Should be UNIQUE and NOT NULL

Contact VARCHAR(30)

Rep_ID VARCHAR(5)



6.

Add a constraint to make sure the Rep_ID value entered in the BOOK_STORES table is a valid value contained in the STORE_REPS table. The Rep_ID columns of both tables were initially created as different datatypes. Does this cause an error when adding the constraint? Make table modifications as needed so that you can add the required constraint.



7.

Change the constraint created in Assignment #6 so that associated rows of the

BOOK_STORES table are deleted automatically if a row in the STORE_REPS table is deleted.



8.

Create a table named REP_CONTRACTS containing the columns listed in the following chart. A composite PRIMARY KEY constraint including the Rep_ID, Store_ID, and Quarter columns should be assigned. In addition, FOREIGN KEY constraints should be assigned to both the Rep_ID and Store_ID columns.



9.

Produce a list of information about all existing constraints on the STORE_REPS table.