Sql 错误979:不是GROUP BY表达式

尝试返回上次联系日期时出错

SELECT CDC.pat_id, MAX(SOC.contact_date), 
FROM hb61.cdcsaar_patients CDC
JOIN clarity.social_hx SOC ON CDC.pat_id=SOC.pat_id
LEFT OUTER JOIN clarity.smoking_cess_hx CESS ON CDC.pat_id=CESS.pat_id
LEFT OUTER JOIN clarity.social_hx_alc_use ALC on CDC.pat_id=ALC.pat_id
GROUP BY SOC.contact_date
;

---

您需要将所选列（在本例中为CDC.pat_id）放在GROUP BY子句上，而不是应用聚合函数的列

SELECT
  CDC.pat_id,
  MAX(SOC.contact_date)
FROM
  hb61.cdcsaar_patients CDC
  JOIN clarity.social_hx SOC ON CDC.pat_id = SOC.pat_id
  LEFT OUTER JOIN clarity.smoking_cess_hx CESS ON CDC.pat_id = CESS.pat_id
  LEFT OUTER JOIN clarity.social_hx_alc_use ALC on CDC.pat_id = ALC.pat_id
GROUP BY
  CDC.pat_id;

---

您需要将未应用聚合函数的任何列放入GROUP BY子句中（在本例中为

CDC.pat\u id

，而不是

SOC.contact\u date

）