Question

我正在查询几个表来获取每个答案的计数，当结果表中找到记录时，此查询正常工作。我想以这样一种方式处理这个查询：如果在结果表中没有找到任何答案或问题的记录，它必须显示该值的计数'0'及其各自的问题和答案。我必须在此查询中进行哪些更改？或者有什么办法，请告诉我？提前谢谢。

这是我的查询。

SELECT s.NAME AS surveyname,
    COUNT(r.answer_id) AS totalAnswer,
    q.id AS questionid,
    q.question AS question,
    a.answer AS answer,
    COUNT(r.textbox) AS totalTextbox,
    COUNT(r.textboxmulti) AS totalTextboxmulti,
    qt.template AS template,
    s.NAME AS surveyname,
    COUNT(r.other) AS other
FROM surveys s
INNER JOIN survey_results AS sr
    ON s.id = sr.survey_id
INNER JOIN results AS r
    ON sr.id = r.surveyresults_id
INNER JOIN questions AS q
    ON r.question_id = q.id
INNER JOIN questiontypes AS qt
    ON q.questiontype_id = qt.id
LEFT JOIN answers AS a
    ON r.answer_id = a.id
WHERE s.id = < cfqueryparam cfsqltype = "cf_sql_integer" value = "#arguments.surveyid#" >
GROUP BY q.id,
    a.id
ORDER BY q.id, a.id a.rank

如果找不到匹配的记录，则应显示如下所示的内容。

surveyname totalanswer qid question answer totaltextbox totaltextboxmulti template totalother
somename     0         1 what ?   yes     0              0              multiple  0
somename     0         1 what ?   no      0              0              multiple  0

如果有匹配的记录，那么它应该在totalanswer或totaltextbox等中显示计数。

Answer 1

尝试添加此COUNT(ifnull(r.other,0)) AS other

    SELECT s.NAME AS surveyname,
    COUNT(r.answer_id) AS totalAnswer,
    q.id AS questionid,
    q.question AS question,
    a.answer AS answer,
    COUNT(r.textbox) AS totalTextbox,
    COUNT(r.textboxmulti) AS totalTextboxmulti,
    qt.template AS template,
    s.NAME AS surveyname,
    COUNT(ifnull(r.other,0)) AS other
FROM surveys s
INNER JOIN survey_results AS sr
    ON s.id = sr.survey_id
INNER JOIN results AS r
    ON sr.id = r.surveyresults_id
INNER JOIN questions AS q
    ON r.question_id = q.id
INNER JOIN questiontypes AS qt
    ON q.questiontype_id = qt.id
LEFT JOIN answers AS a
    ON r.answer_id = a.id
WHERE s.id = < cfqueryparam cfsqltype = "cf_sql_integer" value = "#arguments.surveyid#" >
GROUP BY q.id,
    a.id
ORDER BY a.rank

修改

同样@SlowCoder建议，尝试在结果表上使用LEFT JOIN。

查询结果集为零时如何获取显示记录？

1 个答案: