SELECT c.a,c.b,c.c,c.d,B.g,B.h from ( SELECT distinct a,b,c,d FROM A where b > '02-05-20') c left outer join B on (c.a=B.e)
我觉得如果不损失B、C、D的情况下是行不通的。Yang_(扬帆破浪) 的 SELECT distinct a,b,c,d FROM A where b > '02-05-20' 实际还是没有使A唯一
哦,是呀!SELECT c.a,c.b,c.c,c.d,B.g,B.h from ( SELECT a,min(b) as b,min(c) as c,min(d) as d FROM A where b > '02-05-20' group by a) c left outer join B on (c.a=B.e)
(
SELECT distinct a,b,c,d FROM A where b > '02-05-20') c left outer join B on (c.a=B.e)
SELECT distinct a,b,c,d FROM A where b > '02-05-20'
实际还是没有使A唯一
(
SELECT a,min(b) as b,min(c) as c,min(d) as d FROM A where b > '02-05-20' group by a) c left outer join B on (c.a=B.e)