在数据仓库脚本中出现解析错误

Getting Parse error in the datawarehouse script

我在下面的脚本中遇到错误,它是语句附近某处的解析错误,我不知道错误是什么,有人能告诉我语句有什么问题吗,内部 select 不同的命令是运行 很好,但外部不同的声明不是 运行。

INSERT INTO ccsm.trn_custom_cohorts (person_id, encounter_id, cohort_type, cohort, cohort_val, ts_cohort, dt_create, optional1, optional2)
  SELECT DISTINCT
    person_id,
    encounter_id,
    cohort_type,
    cohort,
    cohort_val,
    cast(ts_cohort AS date),
    sysdate           AS dt_create,
    median            AS optional1,
    jvion_cohort_type as optional2
  from
    (SELECT distinct
       xx_person_id                                                                                   AS person_id,
       xx_encounter_id                                                                                AS encounter_id,
       'Vitals'                                                                                       AS cohort_type,
       mod_optional1                                                                                  AS cohort,
       vital_sign                                                                                     AS cohort_val,
       ISNULL(cast(assessment_time as date), cast(mod_optional_ts1 as date))                   AS ts_cohort,
       'Vitals'                                                                                       as jvion_cohort_type,
       rank()
       OVER (
         PARTITION BY account_identifier, mod_optional1
         ORDER BY ISNULL(cast(assessment_time as date), cast(mod_optional_ts1 as date)) DESC ) AS rank1,
         null                              AS median
     FROM ccsm.stg_vital_signs
     WHERE vital_sign <> '')
  where rank1 = 1;

您没有为子查询设置别名。

WHERE vital_sign <> '') MY_ALIAS