Question

I have a table “Competitor” and here are some of its columns:

Type | Brand | Model | Date | Resolution | etc.

The table will have duplicate Model entries (with obviously same Brand as well, but possibly a different Type (two possible types: ‘ProAV’ and ‘Disti’)). I need to build a query that will output a table like this:

Top (ProAV) | Top (Disti) | Last Occurrence | Brand | Model | Resolution | etc.

Basically I need a query that will get a distinct type, brand, and model, but get a count of how many duplicates were found and put that number in either Top (ProAV) or Top (Disti), whichever Type it has. I would need to pull the most recent (given Date) out of the duplicates, so that I can put its Date as the Last Occurrence field. I hope this makes sense, let me know if it doesn’t.

Answer 1

SELECT SUM(CASE WHEN Type = 'ProAV' THEN 1 ELSE 0 END) AS TopProAV,
       SUM(CASE WHEN Type = 'Disti' THEN 1 ELSE 0 END) AS TopDisti,
       MAX(Date) AS LastOccurence,
       Brand, Model, Resolution
    FROM Competitor
    GROUP BY Brand, Model, Resolution

EDIT: Based on the comment, you could use a subquery or CTE to accomplish what you want. Something like:

WITH cteMaxDate AS (
    SELECT SUM(CASE WHEN Type = 'ProAV' THEN 1 ELSE 0 END) AS TopProAV,
           SUM(CASE WHEN Type = 'Disti' THEN 1 ELSE 0 END) AS TopDisti,
           MAX(Date) AS LastOccurence,
           Brand, Model, Resolution
        FROM Competitor
        GROUP BY Brand, Model, Resolution
)
SELECT md.TopProAV, md.TopDisti,
       md.LastOccurentce, 
       md.Brand, md.Model, md.Resolution,
       c.AdditionalColumn1, c.AdditionalColumn2
    FROM cteMaxDate md
        INNER JOIN Competitor c
            ON md.Brand = c.Brand
                AND md.Model = c.Model
                AND md.Resolution = c.Resolution
                AND md.LastOccurence = c.Date