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select nvl(sum(t.dwxhl),1) from tb_jhde t where
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select nvl(sum(t.dwxhl),1) from tb_jhde t where
zydm=-1ÕâÀï¹ØÐĵÄnvlµÄÓ÷¨£¬nvl£¨arg,value£©´ú±íÈç¹ûÇ°ÃæµÄargµÄֵΪnullÄÇô·µ»ØµÄֵΪºóÃæµÄvalue
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declare
i integer
select nvl(sum(t.dwxhl),1) into i from tb_jhde t where
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