Question

SQL新手，欢迎任何帮助。

任何人都可以就创建以下查询的最佳方法提出建议。

   _hs_eb_code1 = 'bf', then set format = _hs_eb_det1
   _hs_eb_code# = 'bf', then set format = _hs_eb_det#

Repeat until _hs_eb_code# (1-9),

但是，如果_hs_eb_det1的字符长度超过100个字符，则前缀为'*'。另外_hs_eb_code1 ='bf'是一个，而_hs_eb_det1将提供许多结果。

到目前为止，我可以使用案例查询来检查第一部分，然后构建另一个查询。我迷路了。

查询：

 SELECT CASE 
    WHEN LEN(FORMAT) < 100 THEN LEFT(FORMAT,100)
    ELSE '*'+FORMAT 
 END AS FORMAT
FROM (SELECT CASE

           WHEN EXISTS (SELECT _HS_EB_CODE1 FROM DBO.SRC_HBL_CLNT_CAT  WHERE   _HS_EB_CODE1 = 'BF') THEN _HS_EB_DET1 
       WHEN EXISTS (SELECT _HS_EB_CODE2 FROM DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE2 = 'BF') THEN _HS_EB_DET2
             WHEN EXISTS (SELECT _HS_EB_CODE3 FROM DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE3 = 'BF') THEN _HS_EB_DET3     
             WHEN EXISTS (SELECT _HS_EB_CODE4 FROM DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE4 = 'BF') THEN _HS_EB_DET4
           WHEN EXISTS (SELECT _HS_EB_CODE5 FROM DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE5 = 'BF') THEN _HS_EB_DET5
             WHEN EXISTS (SELECT _HS_EB_CODE6 FROM DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE6 = 'BF') THEN _HS_EB_DET6
           WHEN EXISTS (SELECT _HS_EB_CODE7 FROM DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE7 = 'BF') THEN _HS_EB_DET7
           WHEN EXISTS (SELECT _HS_EB_CODE8 FROM DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE8 = 'BF') THEN _HS_EB_DET8
            WHEN EXISTS (SELECT _HS_EB_CODE9 FROM DBO.SRC_HBL_CLNT_CAT WHERE  _HS_EB_CODE9 = 'BF') THEN _HS_EB_DET9
END ) AS FORMAT
    FROM DBO.SRC_TBM_BILLGRP

但我遇到的问题是查询有一对多，因此无法正常工作。什么时候出现（从DBO.SRC_HBL_CLNT_CAT WHERE _HS_EB_CODE1 ='BF'中选择_HS_EB_CODE1）那么_HS_EB_DET1

Answer 1

select case when len(format) > 100 then left(format, 100) + '*' else format end as format from
(select case 'bf' when _hs_eb_code1 then _hs_eb_det1
              when _hs_eb_code2 then _hs_eb_det2
              when _hs_eb_code3 then _hs_eb_det3
              when _hs_eb_code4 then _hs_eb_det4
              when _hs_eb_code5 then _hs_eb_det5
              when _hs_eb_code6 then _hs_eb_det6
              when _hs_eb_code7 then _hs_eb_det7
              when _hs_eb_code8 then _hs_eb_det8
              when _hs_eb_code9 then _hs_eb_det9
              end) as format
    from <yourtable>) a

案例查询无效

1 个答案: