How to print result from sql query with month name - sql-server-2008

Question

I have a SQL query which retrieving count with month.
Ex :
January - 5
February - 2 so on.
What I need to know is, if there are no record for particular month, how to print that month and display its count as 0.
This is my query:
select
DATETNAME(MONTH, c.postTime) as Month, COUNT(c.regNo) as Count
from
Company c
where
DATENAME(YEAR, c.postTime) = 2015
group by
c.postTime
This query returns these results:
MONTH | Count
-----------------
July | 2
August | 1
The result I'm looking for should be:
MONTH | Count
-----------------
January | 0
February| 0
March | 0
April | 0
May | 0
June | 0
July | 2
August | 1
.
.
.
so on...

Answer 1

One way is to drive them from anchor query where all the months' list are written explicitly, then left join your table company:
SELECT m.Name, COUNT(COALESCE(c.regNo, 0)) as Count
FROM
(
VALUES ('Janurary'), ('February'), ('March'),
('April'), ('May'), ('June'),
('July'), ('August'), ('September'),
('October'), ('November'), ('December')
) AS m(Name)
LEFT JOIN Company c ON DATETNAME(MONTH, c.postTime) = m.Name
WHERE DATENAME(YEAR, c.postTime) = 2015
GROUP BY m.Name;
If the table company doesn't have any particular month, it will be shown with count 0.
You can also use a recursive CTE to generate numbers from 1 to 12 and cast these integers to month names:
;WITH CTE
AS
(
SELECT 1 AS n
UNION ALL
SELECT n + 1
FROM CTE
WHERE n < 12
), Months
AS
(
SELECT DATENAME(Month,
DATEADD(Month,
n-1,
CAST('2015-01-01' AS datetime))) AS Name
FROM CTE
)
SELECT m.Name, COUNT(COALESCE(c.regNo, 0)) as Count
FROM Months AS m
LEFT JOIN Company c ON DATETNAME(MONTH, c.postTime) = m.Name
WHERE DATENAME(YEAR, c.postTime) = 2015
GROUP BY m.Name;

Answer 2

SELECT m.Name, COUNT(COALESCE(c.regNo, 0)) as Count
FROM
(
VALUES ('Janurary'), ('February'), ('March'),
('April'), ('May'), ('June'),
('July'), ('August'), ('September'),
('October'), ('November'), ('December')
) AS m(Name)
LEFT JOIN Company c ON DATETNAME(MONTH, c.postTime) = m.Name
AND DATENAME(YEAR, c.postTime) = 2015
GROUP BY m.Name;
Use And instead of "Where" keyword. Then It's working as expected.