How to retrieve data from a single table
Enter and run your own SELECT statements
In these exercises, you’ll enter and run your own SELECT statements.
Write a SELECT statement that returns four columns from the Products table: product_code, product_name, list_price, and discount_percent. Then, run this statement to make sure it works correctly.
Add an ORDER BY clause to this statement that sorts the result set by list price in descending sequence. Then, run this statement again to make sure it works correctly. This is a good way to build and test a statement, one clause at a time.
Write a SELECT statement that returns one column from the Customers table named full_name that joins the last_name and first_name columns.
Format this column with the last name, a comma, a space, and the first name like this:
Sort the result set by last name in ascending sequence.
Return only the customers whose last name begins with letters from M to Z.
NOTE: When comparing strings of characters, ‘M’ comes before any string of characters that begins with ‘M’. For example, ‘M’ comes before ‘Murach’.
3. Write a SELECT statement that returns these columns from the Products table:
The product_name column
The list_price column
The date_added column
Return only the rows with a list price that’s greater than 500 and less than 2000.
Sort the result set in descending sequence by the date_added column.
product_name The product_name column
list_price The list_price column
discount_percent The discount_percent column
discount_amount A column that’s calculated from the previous two columns
discount_price A column that’s calculated from the previous three columns
Round the discount_amount and discount_price columns to 2 decimal places.
Sort the result set by discount price in descending sequence.
Use the LIMIT clause so the result set contains only the first 5 rows.
5. Write a SELECT statement that returns these column names and data from the Order_Items table:
item_id The item_id column
item_price The item_price column
discount_amount The discount_amount column
quantity The quantity column
price_total A column that’s calculated by multiplying the item price by
discount_total A column that’s calculated by multiplying the discount
amount by the quantity
item_total A column that’s calculated by subtracting the discount
amount from the item price and then multiplying by the
Only return rows where the item_total is greater than 500.
Sort the result set by item total in descending sequence.
Work with nulls and test expressions
6. Write a SELECT statement that returns these columns from the Orders table:
order_id The order_id column
order_date The order_date column
ship_date The ship_date column
Return only the rows where the ship_date column contains a null value.
today_unformatted The NOW function unformatted
today_formatted The NOW function in this format:
This displays a number for the day, an abbreviation for the month, and a four-digit year.
8. Write a SELECT statement without a FROM clause that creates a row with these columns:
price 100 (dollars)
tax_rate .07 (7 percent)
tax_amount The price multiplied by the tax
total The price plus the tax
To calculate the fourth column, add the expressions you used for the first and third columns.