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Posted by yicong on 09/20/06 08:51
I want to select one field from a table,but it should on some conditions
which refer to 5 table ,such as A.FILED1=B.FIELD1 AND B.FIELD2=C.FIELD3 AND
....
Should I use case "select sum(a.amount) from a,b,c,... where
a.field1=b.field1 and b.field2=c.field2 and ..." or "select sum(a.amount)
from select b.field1 from select c.field2 from...."?And which case is more
efficiency?
thanks!
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