SQL Server query - Selecting COUNT(*) with DISTINCT

Question

In SQL Server 2005 I have a table cm_production that lists all the code that's been put into production. The table has a ticket_number, program_type, and program_name and push_number along with some other columns.

GOAL: Count all the DISTINCT program names by program type and push number

What I have so far is:

SELECT DISTINCT COUNT(*) AS Count, program_type AS [Type] 
FROM cm_production 
WHERE push_number=@push_number 
GROUP BY program_type

This gets me partway there, but it's counting all the program names, not the distinct ones (which I don't expect it to do in that query). I guess I just can't wrap my head around how to tell it to count only the distinct program names without selecting them. Or something.

Answer 1

Perhaps a subquery that selects distinct names, and the outer query that counts it?

Answer 2

try this:

SELECT
    COUNT(program_name) AS [Count],program_type AS [Type]
    FROM (SELECT DISTINCT program_name,program_type
              FROM cm_production 
              WHERE push_number=@push_number
         ) dt
    GROUP BY program_type

Answer 3

Count all the DISTINCT program names by program type and push number

SELECT COUNT(DISTINCT program_name) AS Count,
  program_type AS [Type] 
FROM cm_production 
WHERE push_number=@push_number 
GROUP BY program_type

DISTINCT COUNT(*) will return a row for each unique count. What you want is COUNT(DISTINCT expression): evaluates expression for each row in a group and returns the number of unique, nonnull values.

Answer 4

SELECT COUNT(DISTINCT program_name) AS Count, program_type AS [Type] 
FROM cm_production 
WHERE push_number=@push_number 
GROUP BY program_type