请教如何实现如下sql查询

[lxw2100]

A表
UID ATTR1 ATTR2
1 A B
2 C D
3 E F
B表
UID ATTR_NAME v1 v2
1 ATTR1 0 1
1 ATTR2 1 0
2 ATTR1 1 0
2 ATTR2 1 1
3 ATTR1 1 1

想要得到以下查询结果：
UID ATTR1 ATTR2
v1 1 B
v2 1 A

UID ATTR1 ATTR2
v1 2 C D
v2 2 D

UID ATTR1 ATTR2
v1 3 E
v2 3 E

请教如何实现？

[CT_LXL]

引用 楼主 lxw2100 的回复:

请教如何实现？

SELECT 'V1' REMARKS,
        B1.UID,
       (SELECT IF(B.V1<>0,A.ATTR1,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR1')ATTR1,
       (SELECT IF(B.V1<>0,A.ATTR2,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR2')ATTR2
FROM( SELECT DISTINCT UID FROM B)B1
UNION ALL
SELECT 'V2' REMARKS,
        B1.UID,
       (SELECT IF(B.V2<>0,A.ATTR1,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR1')ATTR1,
       (SELECT IF(B.V2<>0,A.ATTR2,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR2')ATTR2
FROM( SELECT DISTINCT UID FROM B)B1
ORDER BY UID,REMARKS

[jdk_8_l]

左外连接，右外连接，全外连接，试试

[lxw2100]

引用 1 楼 zlloct 的回复:

[quote=引用 楼主 lxw2100 的回复:] 请教如何实现？

SELECT 'V1' REMARKS,
        B1.UID,
       (SELECT IF(B.V1<>0,A.ATTR1,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR1')ATTR1,
       (SELECT IF(B.V1<>0,A.ATTR2,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR2')ATTR2
FROM( SELECT DISTINCT UID FROM B)B1
UNION ALL
SELECT 'V2' REMARKS,
        B1.UID,
       (SELECT IF(B.V2<>0,A.ATTR1,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR1')ATTR1,
       (SELECT IF(B.V2<>0,A.ATTR2,NULL) FROM A,B WHERE A.UID=B.UID AND B.UID=B1.UID AND B.ATTR_NAME='ATTR2')ATTR2
FROM( SELECT DISTINCT UID FROM B)B1
ORDER BY UID,REMARKS

[/quote] 测试后确实满足需求，多谢！