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Need SQL help

Posted on 2011-02-23
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Last Modified: 2012-05-11
Have the following SQL queries that work fine

select COUNT(*) as AES_18
from students
where grade_level=4 AND Enroll_Status=0 AND SchoolID=5 AND home_room<>'SESO'
<td>~(AES_18)</td>

select COUNT(*) as AES_19
from Sections
where course_number=0400 AND termID=2000 AND SchoolID=5
<td>~(AES_19)</td>

I need to be able to use SQL to perform AES_18/AES_19
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Question by:btcs1
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6 Comments
 
LVL 93

Expert Comment

by:Patrick Matthews
ID: 34965275
SELECT
    (select COUNT(*) 
    from students
    where grade_level=4 AND Enroll_Status=0 AND SchoolID=5 AND home_room<>'SESO') / 
    (select COUNT(*) 
    from Sections
    where course_number=0400 AND termID=2000 AND SchoolID=5) AS Result

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0
 
LVL 26

Expert Comment

by:tigin44
ID: 34965307

select
(
select COUNT(*) as AES_18
from students
where grade_level=4 AND Enroll_Status=0 AND SchoolID=5 AND home_room<>'SESO'
/

select COUNT(*) as AES_19
from Sections
where course_number=0400 AND termID=2000 AND SchoolID=5)
0
 
LVL 6

Expert Comment

by:Rajesh_mj
ID: 34967337
Please consider error handling also.
If the value of AES_19 is Zero, then we will have "Divide by zero error encountered" error.
0
 
LVL 93

Accepted Solution

by:
Patrick Matthews earned 2000 total points
ID: 34968987
Handling the potential zero denominator (good catch!)...



DECLARE @numerator decimal(16, 4), @demoninator decimal(16, 4)

SET @numerator = 
    (select COUNT(*) 
    from students
    where grade_level=4 AND Enroll_Status=0 AND SchoolID=5 AND home_room<>'SESO')

SET @denominator = 
    (select COUNT(*) 
    from Sections
    where course_number=0400 AND termID=2000 AND SchoolID=5)

--If you want the result to be NULL:

SELECT CASE WHEN @denominator <> 0 THEN  @numerator / @denominator ELSE NULL END AS Result

--If you want the result to be zero:

SELECT CASE WHEN @denominator <> 0 THEN  @numerator / @denominator ELSE 0 END AS Result

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0
 
LVL 143

Expert Comment

by:Guy Hengel [angelIII / a3]
ID: 36119873
This question has been classified as abandoned and is closed as part of the Cleanup Program. See the recommendation for more details.
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