多个SELECT命令

Question

我想在我的SQL检索这种表：

Type  Qad (type count)  Correct(No. of item without error)  Accuracy(%) 
    type 1  3         3       100 
    type2   6         3        50 

我curretly尝试使用此查询，但它有一个错误：

SELECT `type` AS 'ReturnType', COUNT(*) AS 'QAd', 
(SELECT COUNT(*) FROM bartran WHERE QASample='2' AND QAErrorID='1' AND `type`=ReturnType AND TimefileDate BETWEEN '2012-01-01' AND '2012-12-31' AS 'Correct', 
(SELECT COUNT(*) FROM bartran WHERE QASample='2' AND QAErrorID='1' AND `type`=ReturnType AND TimefileDate BETWEEN '2012-01-01' AND '2012-12-31')/COUNT(*) * 100) AS 'Accuracy' 
FROM bartran WHERE QASample='2' 
AND TimefileDate BETWEEN '2012-01-01' AND '2012-12-31' 
GROUP BY TYPE; 

我目前这个新的，希望有人能帮助我。谢谢！！

Answer 1

你有失踪查询括号），正确的是：

SELECT `type` AS 'ReturnType', 
     Count(*) AS 'QAd', 
     (SELECT Count(*) 
     FROM bartran 
     WHERE qasample = '2' 
       AND qaerrorid = '1' 
       AND `type` = returntype 
       AND timefiledate BETWEEN '2012-01-01' AND '2012-12-31') AS 
     'Correct', 
     (SELECT Count(*) 
     FROM bartran 
     WHERE qasample = '2' 
       AND qaerrorid = '1' 
       AND `type` = returntype 
       AND timefiledate BETWEEN '2012-01-01' AND '2012-12-31')/Count(* 
     ) * 100 AS 'Accuracy' 
FROM bartran 
WHERE qasample = '2' 
     AND timefiledate BETWEEN '2012-01-01' AND '2012-12-31' 
GROUP BY type; 

好多查询应该是：

SELECT `type` AS 'ReturnType', 
     Count(*) AS 'QAd', 
     Count(CASE 
       WHEN qaerrorid = '1' THEN 1 
       ELSE NULL 
      end) AS 'Correct', 
     Count(CASE 
       WHEN qaerrorid = '1' THEN 1 
       ELSE NULL 
      end)/Count(*) * 100 AS 'Accuracy' 
FROM bartran 
WHERE qasample = '2' 
     AND timefiledate BETWEEN '2012-01-01' AND '2012-12-31' 
GROUP BY type;