请教:sql查找问题?(急用) select A.id, A.username, A.QQ,B.phonefrom T1 A inner join(select id,username,phone1 as phone from T2unionselect id,username,phone2 as phone from T3) B on A.username=B.username 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 select a.id,a.username,a.QQ,b.phone1 as phonefrom T1 ainner join (select * from T2 union all select * from T3) bwhere a.username=b.username select a.id,a.username,a.QQ,b.phone1 as phonefrom T1 ainner join (select * from T2 union all select * from T3) bon a.username=b.username declare @T1 table(id int,username varchar(20),QQ varchar(20))insert @T1 values(1,'u1','2233')insert @T1 values(2,'u2','33445')insert @T1 values(3,'u3','42424')insert @T1 values(4,'u4','243454')insert @T1 values(5,'u5','243545')declare @T2 table(id int,username varchar(20),phone1 varchar(20))insert @T2 values(1,'u1','112230')insert @T2 values(2,'u2','223111')insert @T2 values(3,'u3','445222')declare @T3 table(id int,username varchar(20),phone2 varchar(20))insert @T3 values(1,'u4','111254')insert @T3 values(2,'u5','695422')select a.*,b.phone1 from @T1 a ,@T2 b where a.username=b.usernameunion allselect a.*,c.phone2 from @T1 a ,@T3 c where a.username=c.username 请教,如何获取字段格式? 从数据库中查询的两条数据进行交换,在一个事务中怎样处理??? 女程序员提问:日期函数转换 group by如何筛选每两个钟头的数据 求一语句 求一解决办法,谢谢! 如何修改一个字段的默认值? 请高手路过务必看看:为何MS-SQL2000无法安装? "协调事件和服务器时出现错误,不能调试查询" 迷惑啊!!! 急急急!!!求救---锁的使用! 关于数据库的连接池问题? 请教关于select 语句中的left join 与left outer join 或left inner join 联接方式的区别....
a.id,a.username,a.QQ,b.phone1 as phone
from
T1 a
inner join
(select * from T2 union all select * from T3) b
where
a.username=b.username
a.id,a.username,a.QQ,b.phone1 as phone
from
T1 a
inner join
(select * from T2 union all select * from T3) b
on
a.username=b.username
declare @T1 table(id int,username varchar(20),QQ varchar(20))insert @T1 values(1,'u1','2233')
insert @T1 values(2,'u2','33445')
insert @T1 values(3,'u3','42424')
insert @T1 values(4,'u4','243454')
insert @T1 values(5,'u5','243545')declare @T2 table(id int,username varchar(20),phone1 varchar(20))insert @T2 values(1,'u1','112230')
insert @T2 values(2,'u2','223111')
insert @T2 values(3,'u3','445222')declare @T3 table(id int,username varchar(20),phone2 varchar(20))insert @T3 values(1,'u4','111254')
insert @T3 values(2,'u5','695422')
select a.*,b.phone1 from @T1 a ,@T2 b where a.username=b.username
union all
select a.*,c.phone2 from @T1 a ,@T3 c where a.username=c.username