Oracle supports it definitly :select co1||co2 colalias
from tab1
or select tabalias.a
from ( select a.co1 a from tab1 , tab2 where tab1.pk1 = tab2.pk2 ) tabalias
from tab1
or select tabalias.a
from ( select a.co1 a from tab1 , tab2 where tab1.pk1 = tab2.pk2 ) tabalias
解决方案 »
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