How to count each month without repeating the lines? - mysql

Question

I'm trying to create all months in a query instead of use several lines.
Here is the information:
CREATE TABLE quotes (
id INT,
created_at DATE,
num_policy INT);
INSERT INTO quotes VALUES
( 1, '2014-01-01',1234),
( 2, '2014-02-06',5678),
( 3, '2013-04-24',9123),
( 4, '2013-05-24',4567),
( 5, '2014-06-20',8912);
I tried this query: http://sqlfiddle.com/#!2/2f4f51/5
SET #year := 2014;
SELECT count(*) AS jan FROM `quotes` WHERE (created_at BETWEEN CONCAT( #year, "-01-01") AND CONCAT( #year, "-01-31")) ;
SELECT count(*) AS feb FROM `quotes` WHERE (created_at BETWEEN CONCAT( #year, "-02-01") AND CONCAT( #year, "-02-29")) ;
......
SELECT count(*) AS dem FROM `quotes` WHERE (created_at BETWEEN CONCAT( #year, "-12-01") AND CONCAT( #year, "-12-31")) ;
I'm trying to show all months in one line
|jan| |feb| |mar| |apr| ......
1 1 0 0
Please somebody can help me?
I will appreciate all kind of help.

Answer 1

This could do the magic:
SELECT CASE WHEN MonthSET #year := 2014;
SELECT SUM(CASE WHEN Month(created_at) = 1 THEN 1 ELSE 0 END) AS jan,
SUM(CASE WHEN Month(created_at) = 2 THEN 1 ELSE 0 END) AS feb,
SUM(CASE WHEN Month(created_at) = 3 THEN 1 ELSE 0 END) AS mar,
SUM(CASE WHEN Month(created_at) = 4 THEN 1 ELSE 0 END) AS apr,
SUM(CASE WHEN Month(created_at) = 5 THEN 1 ELSE 0 END) AS may,
SUM(CASE WHEN Month(created_at) = 6 THEN 1 ELSE 0 END) AS jun,
SUM(CASE WHEN Month(created_at) = 7 THEN 1 ELSE 0 END) AS jul,
SUM(CASE WHEN Month(created_at) = 8 THEN 1 ELSE 0 END) AS aug,
SUM(CASE WHEN Month(created_at) = 9 THEN 1 ELSE 0 END) AS sep,
SUM(CASE WHEN Month(created_at) = 10 THEN 1 ELSE 0 END) AS oct,
SUM(CASE WHEN Month(created_at) = 11 THEN 1 ELSE 0 END) AS nov,
SUM(CASE WHEN Month(created_at) = 12 THEN 1 ELSE 0 END) AS `dec`
FROM `quotes`
WHERE YEAR(created_at) = #year
Link to a SQL Fiddle:
http://sqlfiddle.com/#!2/2f4f51/13/1

Answer 2

How about using group by?
SELECT month(created_at), count(*) AS cnt
FROM `quotes`
WHERE (created_at BETWEEN CONCAT( #year, "-01-01") AND CONCAT( #year, "-01-31"))
GROUP BY month(created_at)
ORDER BY 1;
This does produce the values on separate lines. To get them on one line, use conditional aggregation:
SELECT SUM(month(created_at) = 1) as jan,
SUM(month(created_at) = 2) as feb,
. . .
FROM quotes
;WHERE (created_at BETWEEN CONCAT( #year, '-01-01') AND CONCAT( #year, '-01-31'));