Need help with SQL query to show table with all months of the year and associated results

I am trying to display a table of months in a year and against each month display the count of a visits carried out during that month. If there are no visits for a month then it should display 0 in the table.

Below is a query I have made so far.

DECLARE @Visit TABLE (visit_date DATETIME,visit_number VARCHAR(10))
INSERT INTO @Visit (visit_date,visit_number) VALUES
	('2015-01-01 00:00:00','10000/1'),
	('2015-01-02 00:00:00','10000/2'),
	('2015-01-02 00:00:00','10000/3'),
	('2015-01-03 00:00:00','10000/4'),
	('2015-02-02 00:00:00','10000/5'),
	('2015-02-03 00:00:00','10000/6')

SELECT *, DATENAME(MONTH,visit_date) AS MonthName FROM @Visit

DECLARE @Year VARCHAR(4)
SET @Year = '2015'

SELECT Months.Month,COUNT(visit_number) AS Count
FROM (
	SELECT 'January' as Month
    UNION
    select 'February' as Month
    UNION
    select 'March' as Month
    UNION
    select 'April' as Month
    UNION
    select 'May' as Month
    UNION
    select 'June' as Month
    UNION
    select 'July' as Month
    UNION
    select 'August' as Month
    UNION
    select 'September' as Month
    UNION
    select 'October' as Month
    UNION
    select 'November' as Month
    UNION
    select 'December' as Month
) AS Months
LEFT JOIN @Visit ON Months.Month = DATENAME(MONTH,visit_date)
WHERE visit_date  >= @Year + '-01-01 00:00:00' 
AND visit_date <= @Year + '-12-31 00:00:00'
GROUP BY Months.Month
ORDER BY Months.Month

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My example displays the results, but is not showing the months where there are no visits carried out (March - December). I thought that the LEFT JOIN from my months query would show the months where no data is found, but it is not working as expected. Can someone help me fix my problem ?
chriscboyAsked:
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ste5anSenior DeveloperCommented:
Your WHERE condition restricts the output of the LEFT JOIN. Thus it must be part of the JOIN condition. E.g.

 
DECLARE @Visit TABLE
    (
      visit_date DATE ,
      visit_number VARCHAR(10)
    );

INSERT  INTO @Visit
        ( visit_date, visit_number )
VALUES  ( '20150101', '10000/1' ),
        ( '20150102', '10000/2' ),
        ( '20150102', '10000/3' ),
        ( '20150103', '10000/4' ),
        ( '20150202', '10000/5' ),
        ( '20150203', '10000/6' );

SELECT  * ,
        DATENAME(MONTH, visit_date) AS Name
FROM    @Visit;

DECLARE @Year DATE = '20150101';

SELECT  M.MonthNumber ,
        COUNT(visit_number) AS Count
FROM    ( VALUES ( 1 ), ( 2 ), ( 3 ), ( 4 ), ( 5 ), ( 6 ), ( 7 ), ( 8 ), ( 9 ), ( 10 ), ( 11 ), ( 12 ) ) M ( MonthNumber )
	LEFT JOIN @Visit ON M.MonthNumber = MONTH(visit_date)
	AND visit_date >= @Year 
        AND visit_date < DATEADD(YEAR, 1, @Year)
GROUP BY M.MonthNumber
ORDER BY M.MonthNumber;

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chriscboyAuthor Commented:
Thanks for your help!
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Microsoft SQL Server

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