开发中遇到的一个很棘手的问题,向各位高手请教A表:
A B C1 a dm
2 b dm
3 c ods
4 d ods
B表:
A B C11 aa dm
12 bb edw
13 cc dmresult1:x count(A) count(B)dm 4 4
ods 2 2
edw 1 1result2:A B C1 a dm
2 b dm
11 aa dm
13 cc dm
A B C1 a dm
2 b dm
3 c ods
4 d ods
B表:
A B C11 aa dm
12 bb edw
13 cc dmresult1:x count(A) count(B)dm 4 4
ods 2 2
edw 1 1result2:A B C1 a dm
2 b dm
11 aa dm
13 cc dm
FROM (SELECT *
FROM a
UNION ALL
SELECT * FROM b)
GROUP BY c;SELECT *
FROM (SELECT *
FROM a
UNION ALL
SELECT * FROM b)
WHERE c = 'dm';
from (select A,B,C from A
union all
select A,B,C from B)
group by C;SELECT A,B,C
FROM (SELECT A,B,C
FROM A
UNION ALL
SELECT A,B,C FROM B)
WHERE C = 'dm';