ORA-01427：单行子查询返回多行 - 如何修复？

Question

我有一个查询，目的是输出所有具有"PPC" 角色的电子邮件以及这些 PPC 所属的"paygroups"。

• 有很多支付组。
• 每个paygroup 可以有多个PPCs。
• 每个PPC 可能有一个email address 1 和/或一个email address 2。

当我使用测试paygroup(BOX) 时，查询工作正常，但是当我注释该行以查询所有paygroups 以返回所有paygroups 中的所有PPCs 时，我收到错误"single-row subquery returns more than one row" .

SELECT
auth.paygroup,
per.NAME, 
per.email_address AS    "Personal email",
per.email_address2 AS   "Business email"

FROM ps_personal_data per 

INNER JOIN ps_ts_ee_auth auth 
ON auth.emplid=per.emplid

INNER JOIN PS_SMS_SUBSCRB_TBL SUB
ON SUB.SUBSCRIBER_ID = AUTH.PAYGROUP

WHERE 1=1    
 AND SUB.EFFDT = (SELECT max (SUB2.effdt) FROM PS_SMS_SUBSCRB_TBL SUB2 
   WHERE SUB.SUBSCRIBER_ID = SUB2.SUBSCRIBER_ID AND SUB.EFF_STATUS = 'A')  
 AND auth.user_name = (SELECT R1.USER_NAME FROM PS_TS_CONTACT_ROLE R1
                      WHERE 1=1
                      AND R1.contact_role = 'PPC'
                    --AND R1.paygroup = 'BOX' --commenting this line out causes the error. It works fine when line is active
                      AND R1.action_dt = (SELECT MAX (R2.action_dt) 
                                         FROM PS_TS_CONTACT_ROLE R2
                                         WHERE 1=1
                                         AND R1.paygroup = R2.paygroup
                                         AND R1.contact_role =                                   
                                         R2.contact_role))

Answer 1

SELECT
auth.paygroup,
per.NAME, 
per.email_address AS    "Personal email",
per.email_address2 AS   "Business email"

FROM ps_personal_data per 

INNER JOIN ps_ts_ee_auth auth 
ON auth.emplid=per.emplid

INNER JOIN PS_SMS_SUBSCRB_TBL SUB
ON SUB.SUBSCRIBER_ID = AUTH.PAYGROUP

WHERE 1=1    
 AND SUB.EFFDT = (SELECT max (SUB2.effdt) FROM PS_SMS_SUBSCRB_TBL SUB2 
   WHERE SUB.SUBSCRIBER_ID = SUB2.SUBSCRIBER_ID AND SUB.EFF_STATUS = 'A')  
 AND auth.user_name in (SELECT R1.USER_NAME FROM PS_TS_CONTACT_ROLE R1 -- Change = to in
                      WHERE 1=1
                      AND R1.contact_role = 'PPC'
                      AND R1.paygroup = 'BOX' --commenting this line out causes the error. It works fine when line is active
                      AND R1.action_dt = (SELECT MAX (R2.action_dt) 
                                         FROM PS_TS_CONTACT_ROLE R2
                                         WHERE 1=1
                                         AND R1.paygroup = R2.paygroup
                                         AND R1.contact_role =                                   
                                         R2.contact_role))