我有一个表需要被同一个表中的其他响应过滤。我使用以下有效的脚本,但是当“Customer.customer_id”(有时有)重复时,结果会出现偏差。我的问题是是否有更好的方法来重写此代码以避免这种情况,因此它只从“客户”表中选择不同的结果?
下面的示例表应仅返回“两个”响应,因为 customer_id '10' 存在重复条目(基于以下查询)
样品表:
[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
当前查询:
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'