Question

I’m not an expert at SQL and i’m not even sure if this type of query is doable.

I want to return a count(*) for each “MediaTypeID” for each Month based off of “MediaDate”.

Any help would be greatly appreciated!

Thanks.

My Table looks like:

The Table Data looks like:

1 | 1 | Funny Cat Video     | 2006-01-25 00:00:00.000
2 | 1 | Funny Dog Video     | 2006-01-20 00:00:00.000
3 | 2 | Angry Birds Game    | 2006-03-13 00:00:00.000
4 | 4 | Blonde Joke         | 2006-03-16 00:00:00.000
5 | 3 | Goofy Clown Picture | 2006-02-27 00:00:00.000
6 | 2 | Racing Game         | 2006-02-10 00:00:00.000
7 | 1 | Star Wars Video     | 2006-07-15 00:00:00.000

The query would return 12 rows of results for Jan-Dec looking like:

Month | MediaTypeID1Count | MediaTypeID2Count | MediaTypeID3Count | MediaTypeID4Count
Jan   | 400               | 255               | 15                | 65
Feb   | 100               | 25                | 75                | 35
Mar   | 320               | 155               | 50                | 99
Apr   | 56                | 0                 | 98                | 313

Answer 1

This type of data transformation is known as a PIVOT. SQL Server 2005+ has a pivot function that can be implemented:

select month,
  [1] MediaType1_count,
  [2] MediaType2_count,
  [3] MediaType3_count,
  [4] MediaType4_count
from 
(
  select 
    mediatypeid,
    datename(m, mediadate) Month,
    datepart(m, mediadate) monnum
  from yourtable
) src
pivot
(
  count(mediatypeid)
  for mediatypeid in ([1], [2], [3], [4])
) piv
order by monnum

See SQL Fiddle with Demo

If you have an unknown number of values that you want to transpose into columns, then you can use dynamic sql:

DECLARE @cols AS NVARCHAR(MAX),
    @colNames AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT distinct ',' + QUOTENAME(mediatypeid) 
                    from yourtable
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')


select @colNames = STUFF((SELECT distinct ', ' + QUOTENAME(mediatypeid) +' as MediaType' + cast(mediatypeid as varchar(50))+'_Count' 
                    from yourtable
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT month,' + @colNames + ' from 
             (
                select mediatypeid,
                  datename(m, mediadate) Month,
                  datepart(m, mediadate) monnum
                from yourtable
            ) x
            pivot 
            (
                count(mediatypeid)
                for mediatypeid in (' + @cols + ')
            ) p 
            order by monnum'

execute(@query)

See SQL Fiddle with Demo

The result will look like:

|    MONTH | MEDIATYPE1_COUNT | MEDIATYPE2_COUNT | MEDIATYPE3_COUNT | MEDIATYPE4_COUNT |
----------------------------------------------------------------------------------------
|  January |                2 |                0 |                0 |                0 |
| February |                0 |                1 |                1 |                0 |
|    March |                0 |                1 |                0 |                1 |
|     July |                1 |                0 |                0 |                0 |