help for sql query
i have table with name sample in my database it has threecolumns namely words,D1,D2 and it has some data like below
Words D1 D2 D3 pleasure 1 0 1 question 0 0 0 answer 0 1 1 request 1 0 0 scount 1 0 0
so now i want to calculate parameter N00 which 开发者_JAVA技巧means scount=0 and also it should check where 0 exists in D1 and D2 so here for "question" D1=0 D2=0 and scount=0 so the result should be 2 because scount=0 and D1=0 , scount=0 and D2=0 this both satisfy so result is 2 i need sql query fro this please help advance thanks.
If I'm reading correctly you want to know how many records there are with scount = 0 and either D1 or D2 = 0, that's a query like this:
SELECT COUNT(*) as N00 FROM mytable WHERE scount = 0 AND (D1 = 0 OR D2 = 0)
on second pass I think you're trying to count conditions satisfied, that is, +1 when D1 = 0 and +1 when D2 = 0, but only where scount = 0, that's something like this:
SELECT (IF(D1=0,1,0)+IF(D2=0,1,0)) as N00 WHERE scount = 0
Your question doesn't add up. You act as if scount is a column but it is a row. And tbh your question is not making sense. Could you perhaps split this up in separate cases like:
A: (D1 = 0) AND (D2 = 0) -> N00 = X
B: (D1 = 0) AND (D2 = 1) -> N00 = Y
I don't have any idea how to fit in scount in these cases. You cant say the following:
C: (D1 = 0) AND (D2 = 0) AND (scount = 1) -> N00 = Z
This isn't possible because scount is in a different row and has no relation to this row at all.
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