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Databases

Posted by Mohammad Aslam
Mohammad Aslam
6,053 Points

Challenge 1. Using Subquery with IN Clause

Can someone please help with the following. I am having a brain freeze, cant think what to do. The answer is not correct. What do I need to do?

In a car database there is a Model table with columns, ModelID, MakeID and ModelName and a Car table with columns, CarID, ModelID, VIN, ModelYear and StickerPrice. Use a subquery along with IN to list all the Model Names with a Sticker Price greater than $30000

SELECT ModelName FROM Model INNER JOIN Car ON Model.ModelID = Car.ModelID WHERE StickerPrice IN (SELECT StickerPrice FROM Car WHERE StickerPrice > 30000);

ModelName Impala Colorado Cherokee Cherokee Grand Cherokee Grand Cherokee Accord Camry Sienna Sienna Cherokee Accord

2 Answers

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

Here's a few hints:

  • you don't need both a JOIN and a subquery
  • the common field you might use to join on could also be good for a WHERE clause
  • your subquery can return a column other than the one being used to filter results
Jackie Baxter
PLUS
Jackie Baxter
Courses Plus Student 2,801 Points
Jackie Baxter
Jackie Baxter
Courses Plus Student 2,801 Points

I went back and looked at the cheat sheet supplied within the subquery lesson to use for help with this challenge the following syntax example is from that cheat sheet SELECT <columns> FROM <table 1> AS <table 1 alias> INNER JOIN <table 2> AS <table 2 alias> ON <table 1 alias>.<column> = <table 2 alias>.<column>; This allowed me to see what Steven was saying above in that I did not need to use JOINS.