Today, for the first time in 10 years of development with sql server I used a cross join in a production query. I needed to pad a result set to a report and found that a cross join between two tables with a creative where clause was a good solution. I was wondering what use has anyone found in production code for the cross join?
Update: the code posted by Tony Andrews is very close to what I used the cross join for. Believe me, I understand the implications of using a cross join and would not do so lightly. I was excited to have finally used it (I'm such a nerd) - sort of like the time I first used a full outer join.
Thanks to everyone for the answers! Here's how I used the cross join:
SELECT CLASS, [Trans-Date] as Trans_Date,
SUM(CASE TRANS
WHEN 'SCR' THEN [Std-Labor-Value]
WHEN 'S+' THEN [Std-Labor-Value]
WHEN 'S-' THEN [Std-Labor-Value]
WHEN 'SAL' THEN [Std-Labor-Value]
WHEN 'OUT' THEN [Std-Labor-Value]
ELSE 0
END) AS [LABOR SCRAP],
SUM(CASE TRANS
WHEN 'SCR' THEN [Std-Material-Value]
WHEN 'S+' THEN [Std-Material-Value]
WHEN 'S-' THEN [Std-Material-Value]
WHEN 'SAL' THEN [Std-Material-Value]
ELSE 0
END) AS [MATERIAL SCRAP],
SUM(CASE TRANS WHEN 'RWK' THEN [Act-Labor-Value] ELSE 0 END) AS [LABOR REWORK],
SUM(CASE TRANS
WHEN 'PRD' THEN [Act-Labor-Value]
WHEN 'TRN' THEN [Act-Labor-Value]
WHEN 'RWK' THEN [Act-Labor-Value]
ELSE 0
END) AS [ACTUAL LABOR],
SUM(CASE TRANS
WHEN 'PRD' THEN [Std-Labor-Value]
WHEN 'TRN' THEN [Std-Labor-Value]
ELSE 0
END) AS [STANDARD LABOR],
SUM(CASE TRANS
WHEN 'PRD' THEN [Act-Labor-Value] - [Std-Labor-Value]
WHEN 'TRN' THEN [Act-Labor-Value] - [Std-Labor-Value]
--WHEN 'RWK' THEN [Act-Labor-Value]
ELSE 0 END) -- - SUM([Std-Labor-Value]) -- - SUM(CASE TRANS WHEN 'RWK' THEN [Act-Labor-Value] ELSE 0 END)
AS [LABOR VARIANCE]
FROM v_Labor_Dist_Detail
where [Trans-Date] between @startdate and @enddate
--and CLASS = (CASE @class WHEN '~ALL' THEN CLASS ELSE @class END)
GROUP BY [Trans-Date], CLASS
UNION --REL 2/6/09 Pad result set with any missing dates for each class.
select distinct [Description] as class, cast([Date] as datetime) as [Trans-Date], 0,0,0,0,0,0
FROM Calendar_To_Fiscal cross join PRMS.Product_Class
where cast([Date] as datetime) between @startdate and @enddate and
not exists (select class FROM v_Labor_Dist_Detail vl where [Trans-Date] between @startdate and @enddate
and vl.[Trans-Date] = cast(Calendar_To_Fiscal.[Date] as datetime)
and vl.class= PRMS.Product_Class.[Description]
GROUP BY [Trans-Date], CLASS)
order by [Trans-Date], CLASS