Oracle去重查询

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distinct的用法
1.distinct+单个字段，表示对该字段进行去重
2.distinct+column1+column2 表示的是使用多个字段进行联合去重

方法一：GROUP BY分组去重

SELECT T.DOCTOR_ID AS FDOCTORCODE,
      max(T.DOCTOR_NAME) AS FDOCTORNAME,
      max(T.DOCTOR_PHONE) AS FDOCTORPHONE,
      max(T.ORG_ID) AS FORGID,
      max(T.DEPENT_ID) AS FDEPTCODE
 FROM CONSULT_SCHEDULE T
WHERE ORG_ID = '134557'
  AND DEPENT_ID = '1004'
GROUP BY DOCTOR_ID

方法二：

SELECT T.DOCTOR_ID    AS FDOCTORCODE,
       T.DOCTOR_NAME  AS FDOCTORNAME,
       T.DOCTOR_PHONE AS FDOCTORPHONE,
       T.ORG_ID       AS FORGID,
       T.DEPENT_ID    AS FDEPTCODE
  FROM CONSULT_SCHEDULE T,
       (SELECT MAX(ROWID) ROWID2
          FROM CONSULT_SCHEDULE
         WHERE ORG_ID = '416211338'
           AND DEPENT_ID = '1004'
         GROUP BY DOCTOR_ID) T2
 WHERE T.ROWID = T2.ROWID2