一条SQL语句
两个表A,B
其中B有5000条记录，有字段USER_ID,USER_NAME.
A有500条记录有字段USER_ID,USER_TEL.B的USER_ID包含A的
结果显示 USER_NAME,USER_TEL
想查结果有5000条。即有电话就显示电话，没有电话就显示“”。但是所有用户的结果都要有

------解决方案--------------------
select B.USER_NAME,A.USER_TEL from B left join A on A.USER_ID =B.USER_ID
------解决方案--------------------
select b.USER_ID,b.USER_NAME,a.USER_TEL from B as b left join A as a on b.USER_ID = a.USER_ID
------解决方案--------------------

SQL code

select   B.USER_NAME,A.USER_TEL   from   B   left   join   A   on   A.USER_ID   =B.USER_ID

------解决方案--------------------
SQL code
select USER_NAME,isnull(USER_TEL,'') as USER_TEL from B left join A on B.USER_ID=A.USER_ID