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ProdigyOne2k

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SQL Statement - comparing 2 results

Table 1                        Table 2      

AnimalID, COUNT(AnimalID)      AnimalID, Count(AnimalID)

Cat      1                  Cat      4
Dog      4                  Dog       4
Hippo      5            Snake      3
Cow      1                  Frog      4
Frog      2                  Horse      5
                        Sheep      1
                        Pig      3


And I need the resultset to be Table 1 minus Table 2

Cat      -3
Dog      0
Hippo      5
Cow      1
Frog      -2
Snake       -3
Horse      -5
Sheep      -1
Pig      -3

So the first column is an AnimalID, the 2nd is the count of AnimalID.  This information would be the result of Table 1 "SELECT AnimalID, COUNT(AnimalID)FROM Farms WHERE FarmID = 89" and Table 2 "SELECT AnimalID, COUNT(AnimalID)FROM Houses WHERE HouseID = 54"

Any ideas?  I feel like the answer is easy and I should know how to do this but it's not coming to me, help!
Avatar of Jim Horn
Jim Horn
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Probably a number of ways to pull this off, but the one that immediately comes to mind is...
SELECT AnimalID, SUM(the_count) as total
FROM (
   SELECT AnimalID, COUNT(AnimalID) as the_count
   FROM Table1
   GROUP BY AnimalID
   UNION ALL
   SELECT AnimalID, COUNT(AnimalID) * -1 as the_count
   FROM Table2
   GROUP BY AnimalID) t
GROUP BY AnimalID
ORDER BY AnimalID

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Avatar of Chris Luttrell
Chris Luttrell
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ProdigyOne2k - Did you try my solution?  Just curious.
Actually, the FULL OUTER JOIN looks like the superior solution, as when I ran both and viewed the SET STATISTICS IO ON, the UNION ALL executed in 115ms, and the FULL OUTER JOIN executed in 4ms.

SET SHOWPLAN_XML OFF
GO

IF EXISTS (SELECT name FROM sys.tables WHERE name='animals1') 
	DROP TABLE animals1
GO

IF EXISTS (SELECT name FROM sys.tables WHERE name='animals2') 
	DROP TABLE animals2
GO

CREATE TABLE animals1 (AnimalID varchar(15)) 
CREATE TABLE animals2 (AnimalID varchar(15)) 

INSERT INTO animals1 (AnimalID)
VALUES 
	('Cat'), 
	('Dog'), ('Dog'), ('Dog'), ('Dog'), 
	('Hippo'), ('Hippo'), ('Hippo'), ('Hippo'), ('Hippo'),
	('Cow'), 
	('Frog'), ('Frog')

INSERT INTO animals2 (AnimalID)
VALUES 
	('Cat'), ('Cat'), ('Cat'), ('Cat'), 
	('Dog'), ('Dog'), ('Dog'), ('Dog'), 
	('Snake'), ('Snake'), ('Snake'), 
	('Frog'), ('Frog'), ('Frog'), ('Frog'), 
	('Horse'), ('Horse'), ('Horse'), ('Horse'), ('Horse'),
	('Sheep'), 
	('Pig'), ('Pig'), ('Pig')


SET STATISTICS TIME ON

SELECT 'UNION'
SELECT AnimalID, SUM(the_count) as total
FROM (
   SELECT AnimalID, COUNT(AnimalID) as the_count
   FROM animals1
   GROUP BY AnimalID
   UNION ALL
   SELECT AnimalID, COUNT(AnimalID) * -1 as the_count
   FROM animals2
   GROUP BY AnimalID) t
GROUP BY AnimalID

SELECT 'FULL OUTER JOIN'
SELECT  COALESCE(T1.AnimalId,T2.AnimalId) AS AnimalId,
        COALESCE(T1.Cnt,0) - COALESCE(T2.Cnt,0) Results
FROM
	(SELECT AnimalId, COUNT(AnimalId) Cnt FROM animals1 GROUP BY AnimalId) AS T1
FULL OUTER JOIN
	(SELECT AnimalId, COUNT(AnimalId) Cnt FROM animals2 GROUP BY AnimalId) T2
ON T2.AnimalId = T1.AnimalId
GO

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Avatar of ProdigyOne2k
ProdigyOne2k

ASKER

Hey Jimhorn,,
I did not yet but i will check out your last post and let you know how it goes
Thanks!