oracle nvl decode
SELECT
DECODE(ÁÐ,0,'Q'1,'P',2,'O')¡¡AS ret
from dual
--·ÖÎö: µ± ÁÐ=0ʱ,½«"Q"¸³Öµ
--µ± ÁÐ =1ʱ,½«"P"¸³Öµ
--µ± ÁÐ=2ʱ,½«"O"¸³Öµ
--NVL()º¯Êý:
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DECODE(NVL(±äÁ¿ ''),'','-','OK')
//·ÖÎö:
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