This is my table:
id | fk_company
-------------------
1 | 2
2 | 2
3 | 2
4 | 4
5 | 4
6 | 11
7 | 11
8 | 11
9 | 12
The result I want should be string "3, 2, 3, 1" (count of items that belong to each company), because this is just part of my complex query string.
I tried to use this query:
SELECT GROUP_CONCAT(COUNT(id) SEPARATOR ", ")
FROM `table` GROUP BY fk_company;
But I got an error:
Error Number: 1111
Invalid use of group function
I have a feeling COUNT
, MAX
, MIN
or SUM
can't be used in GROUP_CONCAT
. If so, do you know another way to do this?
You need to COUNT()
with GROUP BY
in an inner SELECT
clause first and then apply GROUP_CONCAT()
;
SELECT GROUP_CONCAT(cnt) cnt
FROM (
SELECT COUNT(*) cnt
FROM table1
GROUP BY fk_company
) q;
Output:
| CNT | ----------- | 3,2,3,1 |
Here is SQLFiddle demo.
You can also achieve that by counting the number of commas (or whatever's your separator) in the GROUP_CONCAT:
SELECT (LENGTH(GROUP_CONCAT(DISTINCT fk_company))-LENGTH(REPLACE(GROUP_CONCAT(DISTINCT fk_company), ',', '')))
FROM `table`
GROUP BY fk_company
select GROUP_CONCAT(counts)
from (
select count(id) counts from
table group by fk_company
);
Just use count(id)
SELECT id, COUNT(id) as total
FROM `table` GROUP BY fk_company;
SELECT A,
GROUP_CONCAT(B SEPARATOR '/') AS 'Category',
GROUP_CONCAT(C SEPARATOR '/') AS 'ALIAS_NAME',COUNT('ALIAS_NAME') AS 'Count'
FROM carnews
...
...
GROUP BY 1
ORDER BY 4 DESC
This works well in my case.
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