通過初始調查響應篩選器響應

Question

我有一個表需要通過同一個表內的其他響應進行過濾。我使用下面的腳本，但是當有'Customer.customer_id'（有時候會有）重複時，結果會出現偏差。我的問題是，是否有更好的方法來重寫此代碼以避免這種情況，因此它只從「客戶」表中選擇不同的結果？

因爲有重複的條目下面的示例表應該只返回「兩個的迴應CUSTOMER_ID「10」（下面的基於查詢）

樣品表：

[res_id] [question_id] [customer_id] [survey_id] [res_answer] 
    1   20    10   155   male 
    1   20    11   155   male 
    1   20    10   155   male 
    1   20    12   155   female 

當前查詢：

SELECT 
    Responses.res_id AS responseID 
    ,Responses.res_col AS answer 
    ,Responses.res_created AS dateCreated 
    ,Responses.res_notes AS note 
    ,Responses.question_id AS questionID 
    ,Responses.customer_id AS customerID 
    ,Responses.res_answer AS subQuestion 
    ,Responses.survey_id AS surveyID 
    ,Responses.res_void AS void 
    ,Customer.res_answer AS filter 
FROM 
    Responses, Responses AS Customer 
WHERE 
    rs.customer_id = Customer.customer_id 
AND 
    Responses.survey_id ='155' 
AND 
    Customer.survey_id = '155' 
AND 
    Responses.question_id = '20'      

AND CAST(Customer.res_answer AS VARCHAR(500)) = 'male' 
AND Responses.res_void = '0' 

Answer 1

鮮明如果沒有2005年那麼GROUP BY

支持

SELECT Distinct 
    Responses.res_id AS responseID 
    ,Responses.res_col AS answer 
    ,Responses.res_created AS dateCreated 
    ,Responses.res_notes AS note 
    ,Responses.question_id AS questionID 
    ,Responses.customer_id AS customerID 
    ,Responses.res_answer AS subQuestion 
    ,Responses.survey_id AS surveyID 
    ,Responses.res_void AS void 
    ,'male' 
FROM Responses 
WHERE Responses.survey_id ='155' 
    AND Responses.question_id = '20' 
    AND Responses.res_void = '0'     
    AND exists (select 1 from Responses c 
       where c.res_answer = 'male' 
       and c.survey_id = '155' 
       and c.ID = Responses.ID)