无法识别子查询中“选择”附近的输入

Posted 2023-04-18

【中文标题】无法识别子查询中“选择”附近的输入

【英文标题】：cannot recognize input near 'select' in subquery

【发布时间】：2016-09-05 17:38:33

【问题描述】：

SELECT 
    (case TRIM(T.tactictype)
        WHEN  'Economics' THEN
            (select economic_tactic_id from cfext.economic_tactics E where LOWER(E.economic_tactic_name) = LOWER(T.tacticname) )
        WHEN  'Cyber' THEN
            (select cyber_tactic_id from cfext.cyber_tactics E where LOWER(E.cyber_tactic_name) = LOWER(T.tacticname) )
    end) AS tacticid 
FROM cfext.banking_crreport_allfiles T
LIMIT 50;

我正在尝试运行上述查询，但出现以下错误。 有人可以帮忙吗？

失败：ParseException line 4:1 无法识别表达式规范中“select”“economic_tactic_id”“from”附近的输入

【参考方案1】：

尝试使用

SELECT (case TRIM(T.tactictype) WHEN 'Economics' THEN (select E.economic_tactic_id from cfext.economic_tactics E 
    where LOWER(E.economic_tactic_name) = LOWER(T.tacticname) ) 
WHEN 'Cyber' THEN (select E.cyber_tactic_id from cfext.cyber_tactics E where LOWER(E.cyber_tactic_name) = LOWER(T.tacticname) ) end) AS tacticid 
FROM cfext.banking_crreport_allfiles T LIMIT 50;

【参考方案2】：

SELECT (case TRIM(T.tactictype)
     WHEN 'Economics' THEN
      (select et.economic_tactic_id
         from cfext.economic_tactics et
        where LOWER(et.economic_tactic_name) = LOWER(T.tacticname))
     WHEN 'Cyber' THEN
      (select e.cyber_tactic_id
         from cfext.cyber_tactics e
        where LOWER(e.cyber_tactic_name) = LOWER(T.tacticname))
   end) AS tacticid`enter code here` FROM cfext.banking_crreport_allfiles T LIMIT 50;

【参考方案3】：

Hive 不支持 SELECT 子句中的子查询。你需要改写逻辑：

SELECT COALESCE(E.economic_tactic_id, C.cyber_tactic_id) as tacticid 
FROM cfext.banking_crreport_allfiles T LEFT JOIN
     cfext.economic_tactics E 
     ON LOWER(E.economic_tactic_name) = LOWER(T.tacticname) AND
        TRIM(T.tactictype) = 'Economics' LEFT JOIN
     cfext.cyber_tactics C
     ON LOWER(C.cyber_tactic_name) = LOWER(T.tacticname) AND
        TRIM(T.tactictype) = 'Cyber';