尝试子查询时出现不明确的列名错误

Question

提示为假设风险“1”设施每年至少需要进行 3 次类型检查。显示 2013 年未能满足此要求且至少有 1 个 Failed Canvass-type inspection.Show 设施名称以及 2013 年有多少 Canvass 检查的设施。提示：使用子查询

这是我的代码

SELECT DBAName, COUNT(*)
FROM FoodInspectionOriginal, Organization
WHERE Risk = 1 AND [Inspection Type] IN (SELECT [Inspection Type] FROM FoodInspectionOriginal WHERE [Inspection Type] = 'Canvass' AND [Inspection Date] = Year(2013))
GROUP BY DBAName;

我得到的是输出

Msg 209, Level 16, State 1, Line 3

Ambiguous column name 'Risk'.

Answer 1

我只会使用聚合。假设 table foodinspectionoriginal 的以下 table 结构：

dbaname           -- name of the facility
inspection_date   
inspection_type   -- "Canvass", ...
inspection_status -- "successful", "failed"

查询可以这样表述：

select dbaname,
    sum(case when inspection_type = 'Canvass' and inspection_status = 'failed' then 1 else 0 end) as cnt_failed_canvass
from foodinspectionoriginal
where 
    risk = 1 
    and inspection_date >= '20130101' 
    and inspection_date <  '20140101'
group by dbaname 
having 
    count(*) < 3 
    and sum(case when inspection_type = 'Canvass' and inspection_status = 'failed' then 1 else 0 end) > 0

尝试子查询时出现不明确的列名错误

Getting an Ambiguous column name error when trying to subquery

sql

sql-server

subquery

aggregate-functions

having-clause