嵌套選擇或內部聯接包括來自另一個表的行

我有一個非常複雜的select語句，它使用內部聯接從表中返回統計表（將其視爲答案庫 - 下面的複雜選擇語句）。嵌套選擇或內部聯接包括來自另一個表的行

這些答案與名爲Questions_Bank_AnswerChoices（存儲所有問題）的表相關。

我試圖首先從問題（從表Questions_Bank_AnswerChoices）中提取問題，然後將它們與統計信息（下面的複雜語句）進行匹配。下面的複雜聲明拉動了統計數據，但除非得到答案，否則不會提出問題。

因此，如果沒有人回答question1，那麼問題一將不會顯示在統計數據中，因爲它不包含在答案表中（bc沒有人回答它）。

我該如何做到這一點？我認爲我需要外連接？

複雜的SELECT語句：

WITH tbl as (
    SELECT 
     Questions_Bank.QuestionID, Questions_Bank.QuestionName, 
     REPLACE(Schools_Answers_Items.AnswerValue, '? ', ', ') as AnswerValue, 
     COUNT(Schools_Answers_Items.SchoolsAnswersItemID) AS CountAnswer, 
     Schools_Answers_Items.SchoolID 
    FROM Questions_Bank 
    INNER JOIN Schools_Answers_Items 
    ON Questions_Bank.QuestionID = Schools_Answers_Items.QuestionID 
    LEFT OUTER JOIN Schools_Answers 
    ON Schools_Answers_Items.SchoolsAnswerID = Schools_Answers.SchoolsAnswerID 
    WHERE (Questions_Bank.QuestionID = 1108) 
    AND (Schools_Answers.SchoolID = 103) 
    GROUP BY 
     Schools_Answers_Items.SchoolID,   
     Schools_Answers_Items.AnswerValue, 
     Questions_Bank.QuestionID, 
     Questions_Bank.QuestionName 
) 
SELECT 
    QuestionID, QuestionName, AnswerValue, CountAnswer, 
    SUM(CountAnswer) OVER() AS CountAllAnswers 
FROM tbl

來源

2012-08-15 user1601804

嘗試修改此

INNER JOIN Schools_Answers_Items 
    ON Questions_Bank.QuestionID = Schools_Answers_Items.QuestionID

到

LEFT OUTER JOIN Schools_Answers_Items 
    ON Questions_Bank.QuestionID = Schools_Answers_Items.QuestionID

，你可能要刪除此

AND (Schools_Answers.SchoolID = 103)

或與此

AND (Schools_Answers.SchoolID = 103 OR Schools_Answers.SchoolID IS NULL)

更換試試這個：

SELECT 
     Questions_Bank.QuestionID, Questions_Bank.QuestionName, 
     REPLACE(Schools_Answers_Items.AnswerValue, '? ', ', ') as AnswerValue, 
     Schools_Answers_Items.SchoolID 
    FROM Questions_Bank 
    LEFT OUTER JOIN Schools_Answers_Items 
    ON Questions_Bank.QuestionID = Schools_Answers_Items.QuestionID 
    LEFT OUTER JOIN Schools_Answers 
    ON Schools_Answers_Items.SchoolsAnswerID = Schools_Answers.SchoolsAnswerID 
    WHERE Schools_Answers_Items.SchoolID

來源

2012-08-15 23:48:15 Jim

這並不工作，但我認爲我們是在正確的軌道上。該行：「ON Questions_Bank.QuestionID = Schools_Answers_Items.QuestionID」用這麼多詞彙表示只在該情況下加入（但有時Schools_Answers_Items.QuestionID不存在，因爲它沒有被回答），但我確實認爲外部會修復它？ – user1601804 2012-08-16 19:23:52

LEFT OUTER JOIN應包含JOIN左邊部分表格中的所有內容，在本例中爲Questions_Bank。我會將計數字段和分組取下來，然後嘗試一下「WHERE SchoolID IS NULL」以查看是否在沒有學校答案的情況下提出任何問題。 – Jim 2012-08-16 19:49:02

嵌套選擇或內部聯接包括來自另一個表的行

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