从 SQL 结果中删除重复行

Question

这是我从ORACLE DB 获取结果的 SQL 查询

SELECT U."UID", 
CONCAT(CONCAT(U.LNAME, ', '), U.FNAME) AS UNAME,
M.NAME,
(SELECT COUNT(LH."UID") FROM DRUPAL_SYS.LOGIN_HISTORY LH WHERE LH."UID"=U."UID" ) AS VIEWS_COUNT,
L.LOGIN as "ACCESS" FROM DRUPAL_SYS.USERS U INNER JOIN DRUPAL_SYS.LOGIN_HISTORY L ON L."UID" = U."UID"
INNER JOIN ABC_WEBAPP.MEMBER_USER_ROLE MUR ON MUR.USER_ID=U.MDES_ID AND MUR.MEMBER_ID LIKE '%' 
INNER JOIN ABC_WEBAPP.MEMBER M ON M.ID=MUR.MEMBER_ID WHERE U.LOGIN != 0 AND U."UID">1 ORDER BY L."LOGIN" ASC`

它给出的结果是重复的names

但我的预期结果应该是这样的

Answer 1

SELECT U."UID", 
CONCAT(CONCAT(U.LNAME, ', '), U.FNAME) AS UNAME,
M.NAME,
(SELECT COUNT(LH."UID") FROM DRUPAL_SYS.LOGIN_HISTORY LH WHERE LH."UID"=U."UID" ) AS VIEWS_COUNT,
MAX(L.LOGIN) as "ACCESS" FROM DRUPAL_SYS.USERS U 
INNER JOIN DRUPAL_SYS.LOGIN_HISTORY L ON L."UID" = U."UID"
INNER JOIN ABC_WEBAPP.MEMBER_USER_ROLE MUR ON MUR.USER_ID=U.MDES_ID AND MUR.MEMBER_ID LIKE '%' 
INNER JOIN ABC_WEBAPP.MEMBER M ON M.ID=MUR.MEMBER_ID WHERE U.LOGIN != 0 AND U."UID">1
ORDER BY L."LOGIN" ASC`
GROUP BY UNAME, MNAME

将L.LOGIN 更改为MAX(L.LOGIN) 并添加GROUP BY 子句

Answer 2

SELECT U."UID", 
CONCAT(CONCAT(U.LNAME, ', '), U.FNAME) AS UNAME,
M.NAME,
(SELECT COUNT(LH."UID") FROM DRUPAL_SYS.LOGIN_HISTORY LH WHERE LH."UID"=U."UID" ) AS VIEWS_COUNT,
L.LOGIN as "ACCESS" FROM DRUPAL_SYS.USERS U INNER JOIN DRUPAL_SYS.LOGIN_HISTORY L ON L."UID" = U."UID"
INNER JOIN ABC_WEBAPP.MEMBER_USER_ROLE MUR ON MUR.USER_ID=U.MDES_ID AND MUR.MEMBER_ID LIKE '%' 
INNER JOIN ABC_WEBAPP.MEMBER M ON M.ID=MUR.MEMBER_ID WHERE U.LOGIN != 0 AND U."UID">1 GROUP BY UNAME ORDER BY L."LOGIN" ASC`

Answer 3

为了每个UID 和UNAME 获得一个结果行，您需要按这些字段分组。

GROUP BY UID, UNAME

然后为所有剩余的字段决定显示哪个值。例如。你有四条记录“2689 kaila, piyush”，你想显示哪个名字？首先？最后？最大值？ ...观看次数相同；最大值？总和？访问列也是同样的问题。

例子：

select uid, uname, max(name), max(views_count), max(access)
from (<your query here>) query
group by uid, uname;

复制粘贴（删除了 ORDER BY 子句）：

select uid, uname, max(name), max(views_count), max(access)
from 
(
  SELECT U."UID", 
  CONCAT(CONCAT(U.LNAME, ', '), U.FNAME) AS UNAME,
  M.NAME,
  (SELECT COUNT(LH."UID") FROM DRUPAL_SYS.LOGIN_HISTORY LH WHERE LH."UID"=U."UID" ) AS VIEWS_COUNT,
  L.LOGIN as "ACCESS" FROM DRUPAL_SYS.USERS U INNER JOIN DRUPAL_SYS.LOGIN_HISTORY L ON L."UID" = U."UID"
  INNER JOIN ABC_WEBAPP.MEMBER_USER_ROLE MUR ON MUR.USER_ID=U.MDES_ID AND MUR.MEMBER_ID LIKE '%' 
  INNER JOIN ABC_WEBAPP.MEMBER M ON M.ID=MUR.MEMBER_ID WHERE U.LOGIN != 0 AND U."UID">1
) query
group by uid, uname;