1樓：匿名使用者
select a.userid, a.username, case when b.
depname is null ‘不存在' else '存在' end as 部門是否存在 from a left outer join b on a.depid = b.depid
2樓：大神神風
select a.userid,a.username,b.
depid from userinfo a left join dept b on a.depid=b.depid
查詢出來根據b.depid是否為null來判斷是否存在...
3樓：齊文
select a.userid, a.username,decode(nvl(b.depid,0),0, ‘不存在', '存在' ) as 部門是否存在
from a, b
where a.depid = b.depid(+)
4樓：手機使用者
select userid,username,depid,depi***ists=(case (select count(0) from b where a.depid=b.depid) when 0 then '不存在' else '存在' end) from a
5樓：匿名使用者
select a.userid, a.username, decode(b.deptid,null,'否','是')is_exist
from a left outer join b on a.depid = b.depid
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如果判斷VFP的SQL查詢語句是否找到了記錄
先要把成績表新增在資料環境中。查詢的 select 學號,成績 from 成績 where 學號 thisform.txt1.value into cussor temp if found thisform.grid1.recordsource temp else thisform.grid1 沒有...