sql - 引起ORA-01790的案例: expression must have same datatype as corresponding expression error

Question

我收到了ORA-01790:表达式必须具有与相应的表达式错误消息相同的数据类型。下面是我正在使用的SQL。是CASE语句导致此问题吗？我是sql的新手，这是我第一次尝试使用UNION语句。我尝试了联接而不是UNION，但是尝试的任何联接都会导致Prior_amt字段为空。谢谢您的帮助........

SELECT 
    pa.BUSINESS_UNIT as BUS_UNIT, 
    pa.DESCR AS DESCRIPT,
    pdr.DEPTID AS DEPTID, 
    pdr.ASSET_ID AS ASSET_NO, 
    pdr.ACCOUNT_AD AS ACCT_AD, 
    pdr.BOOK AS BOOK,

    MAX(CASE WHEN (pdr.FISCAL_YEAR =2014 AND pdr.ACCOUNTING_PERIOD =11) THEN  pdr.DEPR END) as CURRENT_AMT,
    MAX(CASE WHEN (pdr.FISCAL_YEAR =2104 AND pdr.ACCOUNTING_PERIOD =10) THEN pdr.DEPR  END) as PRIOR_AMT,

    '' AS ACCT_DE,
    '' AS JRNL_ID,
    '' AS JRNL_DT

    FROM PS_ASSET pa

    INNER JOIN PS_DEPR_RPT pdr 
    ON pa.ASSET_ID = pdr.ASSET_ID
    AND pa.BUSINESS_UNIT = pdr.BUSINESS_UNIT

    WHERE 
    pa.BUSINESS_UNIT='A0465'
    AND pdr.BOOK='PERFORM'
    AND ((pdr.FISCAL_YEAR=2014 AND pdr.ACCOUNTING_PERIOD=11) 
    OR (pdr.FISCAL_YEAR=2014 AND pdr.ACCOUNTING_PERIOD=10))

    group by
    pa.business_unit,
    pa.descr,
    pdr.deptid,
    pdr.asset_id,
    pdr.account_ad,
    pdr.book

UNION ALL

    select
    '' as BUS_UNT,
    '' AS DESCRIPT,
    '' AS DEPTID, 
    '' AS ACCT_AD, 
    '' AS BOOK,
    '' AS CURRENT_AMT,
    '' AS PRIOR_AMT,
    pdl.asset_id AS ASSET_NO,
    pdl.account AS ACCT_DE,
    pdl.journal_id AS JRNL_ID,
    pdl.journal_date AS JRNL_DT

    from ps_dist_ln pdl

    where
    book = 'PERFORM'
    and business_unit = 'A0465'
    and fiscal_year = 2014
    and accounting_period = 11
    and distribution_type = 'DE'

Answer 1

您的问题是您在联合的每一半中都以不同的顺序放置了列。列必须以相同的顺序在两个半部分之间匹配。这与CASE表达式无关。

另外，在您编写2104的位置，可能应该是2014年。