[thelist] Calculating weighted averages
r937
rudy at r937.com
Sat Jul 14 15:13:03 CDT 2007
if a student has not taken a particular exam, there will be no row in the
test table for that student for that exam
thus, since it's a LEFT OUTER JOIN, all columns from the test table in the
query will be null for this situation
consequently, computation involving test.score will be null too
but you knew all that ;o)
the answer to your question is the COALESCE function
note, though, that to show the word "incomplete" you are showing a string,
consequently you may have to CAST the computation to CHAR or VARCHAR
... COALESCE(CAST(ROUND(...) AS CHAR), 'incomplete') as Score
rudy
http://r937.com/
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