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Databases Querying Relational Databases Set Operations Set Operations

Georgina Wise
Georgina Wise
1,774 Points
Posted by Georgina Wise
Georgina Wise
1,774 Points

Does a WHERE clause only appear at the end of a query or does it have to go both sides of the set function?

Hi All,

Following the videos on SET OPERATIONS, Andrew mentioned you should only need to put the WHERE or ORDER BY clause at the end of the query. However, in code challenge 2 the WHERE clause must appear on both sides of the set operator so am a little confused?

I thought the answer should look like this:

SELECT name FROM Fruit 
UNION 
SELECT name FROM Vegetable 
WHERE Name BETWEEN 'A' AND 'L';

But the answer is:

SELECT name FROM Fruit 
WHERE name BETWEEN 'A' AND 'L' 
UNION 
SELECT name FROM Vegetable 
WHERE Name BETWEEN 'A' AND 'L';

1 Answer

Becky Hirsch
Becky Hirsch
14,069 Points
Becky Hirsch
Becky Hirsch
14,069 Points

From what I understand the WHERE needs to be in both but you only need to order it once (as with ORDER BY). I found this explanation at 3:25 in the video "Union Operations".I hope this helps!