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SELECT id HAVING maximum count of id

Have a products table with item_id and color_id. I'm trying to get the color_id with the most non-null instances.

This fails:

SELECT color_id 
  FROM products 
 WHERE item_id=1234 
 GROUP BY item_id 
HAVING MAX(COUNT(color_id))

with

Invalid use of group function

This

SELECT color_id, COUNT(color_id)
  FROM products 
 WHERE item_id=1234 
 GROUP BY item_id

Returns

color_id count
1, 323
2, 122
3, 554

I am looking for color_id 3, which has the most instances.

Is there a quick and easy way of getting what I want without 2 queries?

like image 905
a coder Avatar asked Jan 10 '13 01:01

a coder


People also ask

Can I use max count ()) in SQL?

And the short answer to the above question is, no. You can't. It is not possible to nest aggregate functions.

How do I find the max ID in SQL?

To find the maximum value of a column, use the MAX() aggregate function; it takes a column name or an expression to find the maximum value. In our example, the subquery returns the highest number in the column grade (subquery: SELECT MAX(grade) FROM student ).

What is Count ID in SQL?

In this case, COUNT(id) counts the number of rows in which id is not NULL .

How do I find the maximum number of columns in SQL?

To get one row with the highest count, you can use ORDER BY ct LIMIT 1 : SELECT c. yr, count(*) AS ct FROM actor a JOIN casting c ON c. actorid = a.id WHERE a.name = 'John Travolta' GROUP BY c.


3 Answers

SELECT color_id AS id, COUNT(color_id) AS count 
FROM products 
WHERE item_id = 1234 AND color_id IS NOT NULL 
GROUP BY color_id 
ORDER BY count DESC
LIMIT 1;

This will give you the color_id and the count on that color_id ordered by the count from greatest to least. I think this is what you want.


for your edit...

SELECT color_id, COUNT(*) FROM products WHERE color_id = 3;
like image 183
matt walters Avatar answered Oct 06 '22 00:10

matt walters


SELECT color_id
FROM
    (
        SELECT  color_id, COUNT(color_id) totalCount
        FROM    products 
        WHERE   item_id = 1234 
        GROUP   BY color_id 
    ) s
HAVING totalCount = MAX(totalCount)

UPDATE 1

SELECT  color_id, COUNT(color_id) totalCount
FROM    products 
WHERE   item_id = 1234 
GROUP   BY color_id 
HAVING  COUNT(color_id) =
(
  SELECT  COUNT(color_id) totalCount
  FROM    products 
  WHERE   item_id = 1234 
  GROUP   BY color_id 
  ORDER BY totalCount DESC
  LIMIT 1  
)
  • SQLFiddle Demo (having tie)
like image 38
John Woo Avatar answered Oct 05 '22 23:10

John Woo


SELECT 
  color_id, 
  COUNT(color_id) AS occurances
FROM so_test
GROUP BY color_id
ORDER BY occurances DESC
LIMIT 0, 1

Here is a sample fiddle with a basic table that shows it working: sql fiddle

like image 21
drneel Avatar answered Oct 06 '22 00:10

drneel