Question

我必须通过比较两个ID列中的数据来显示信息，一列有'ALL'而数字是ID，而另一列只有ID作为ID。我的问题是，我无法将字符和数字列与数字列进行比较。所以我正在使用CASE WHEN。

如果值为“ALL”，则在输出中显示“ALL”，否则显示匹配记录的名称。

以下是代码：

CASE
  WHEN secorg.org_id = 'ALL' THEN 'ALL'
  WHEN secorg.org_id = progmap.org_id THEN secorg.org_name
END AS org_name,

条件是：'secorg.org_id = progmap.org_id'，它基于id，如果id相同，我必须显示secorg.org_name。

以下是整个查询：

SELECT distinct program_id,
                prog_name,
                case
                  when Eitc_Active_Switch = '1' then 'ON'
                  when Eitc_Active_Switch = '0'then 'OFF'
                End as Prog_Status,
                progmap.client_id,
                case
                  when secorg.org_id = 'ALL' then 'ALL'
                  --when secorg.org_id = progmap.org_id then secorg.org_name
                  else secorg.org_name
                end as org_name,
                case
                  when prog.has_post_calc_screen = 'True' then 'True'
                  Else 'False'
                End as Referal_ID,
                case
                  when progmap.program_ID IN ( 'AMC1931', 'AMCABD', 'AMCMNMI',
                                               'AMC' )
                       And sec.calwinexists_ind = '1' then 'Yes'
                  when progmap.program_ID IN ( 'AMC1931', 'AMCABD', 'AMCMNMI',
                                               'AMC' )
                       And sec.calwinexists_ind = '0'then 'No'
                  when progmap.program_ID NOT IN (
                       'AMC1931', 'AMCABD', 'AMCMNMI', 'AMC' ) then
                  'N/A'
                End as calwin_interface,
                sec.Client_name
FROM   ref_programs prog (nolock)
       LEFT OUTER JOIN ref_county_program_map progmap (nolock)
         ON progmap.program_id = prog.prog_id
            AND progmap.CLIENT_ID = prog.CLIENT_ID
       INNER join sec_clients sec (nolock)
         on sec.client_id = progmap.Client_id
       Inner join sec_organization secorg (nolock)
         on secorg.org_id = progmap.org_id

Answer 1

为什么不将数字列转换为varchar列？

如果你正在使用SQL SERVER，你可以这样做：

CONVERT(VARCHAR,secorg.org_id) = CONVERT(VARCHAR,progmap.org_id)

当'ALL'和数字的列都是'All'时，你必须对实例进行外连接，因为它不能内连接到另一个表。

对于基于上面代码的快速修复，您只需将第二个WHEN子句更改为如此（再次假设您使用的是MS SQL SERVER）：

WHEN CONVERT(VARCHAR,secorg.org_id) = CONVERT(VARCHAR,progmap.org_id) THEN secorg.org_name

尝试将此作为您的查询：

SELECT DISTINCT 
    program_id, 
    prog_name,
    CASE Eitc_Active_Switch
        WHEN '1' THEN 'ON'
        ELSE 'OFF'
    END AS Prog_Status,
    progmap.client_id,
    ISNULL(secorg.org_name,'ALL') AS org_name,
    CASE prog.has_post_calc_screen
        WHEN 'True' THEN 'True'
        ELSE 'False'
    END AS Referal_ID,
    CASE WHEN progmap.program_ID IN ('AMC1931','AMCABD','AMCMNMI','AMC') AND sec.calwinexists_ind = '1' THEN
        'Yes'
        WHEN progmap.program_ID IN ('AMC1931','AMCABD','AMCMNMI','AMC') AND sec.calwinexists_ind = '0' THEN
        'No'
        WHEN progmap.program_ID NOT IN ('AMC1931','AMCABD','AMCMNMI','AMC') THEN
        'N/A'
    END AS calwin_interface,
    sec.Client_name
FROM
    ref_programs prog (nolock)
LEFT OUTER JOIN ref_county_program_map progmap (nolock) ON progmap.program_id = prog.prog_id AND progmap.CLIENT_ID = prog.CLIENT_ID
INNER JOIN sec_clients sec (nolock) ON sec.client_id = progmap.Client_id
LEFT OUTER JOIN sec_organization secorg (nolock) ON CONVERT(VARCHAR,secorg.org_id) = CONVERT(VARCHAR,progmap.org_id)

Answer 2

案例陈述很好，它的字段别名很糟糕

     END As org_name

像secorg.org_name这样的多部分别名将不起作用

在SQL语句中使用CASE WHEN

2 个答案: