在另一个查询中使用mysql_query结果

Question

以下是我正在执行的查询。但出于某种原因，$ MachineQuery没有得到结果。我认为它与查询中使用$ q1有关，但我不知道为什么。 任何想法？

$q1 =mysql_query("SELECT DISTINCT SymptomID 
FROM Tree 
WHERE SymptomID NOT IN (SELECT DISTINCT SymptomID 
         FROM Tree 
         WHERE LBNodeID = 0 OR RBNodeID = 0)") 

$MachineQuery = mysql_query("SELECT DISTINCT M.MachineID, M.MachineName 
           FROM Machines M, Systems Sys, Symptoms Sym 
           WHERE M.MachineID = Sys.MachineID AND Sys.SystemID 
           =Sym.SystemID AND Sym.SymptomID IN ($q1) 

Answer 1

的问题是，$q1是一个PHP的资源。它不是查询，数组，字符串或其他任何东西。因此，您需要将数据“转换”为更适合您的类型。

这里是我的解决方案：

$q1 =mysql_query("SELECT DISTINCT SymptomID 
    FROM Tree 
    WHERE SymptomID NOT IN (SELECT DISTINCT SymptomID 
         FROM Tree 
         WHERE LBNodeID = 0 OR RBNodeID = 0)"); 
$list = array(); 
while ($row = mysql_fetch_array($q1)) { 
    $list[] = $row[0]; 
} 
$fullList = join(',', $list); 

$MachineQuery = mysql_query("SELECT DISTINCT M.MachineID, M.MachineName 
           FROM Machines M, Systems Sys, Symptoms Sym 
           WHERE M.MachineID = Sys.MachineID AND Sys.SystemID 
           =Sym.SystemID AND Sym.SymptomID IN ($fullList) 

这样，你可以重用的结果，而不必再次运行该查询。

Answer 2

我想尝试

$MachineQuery = mysql_query("SELECT DISTINCT M.MachineID, M.MachineName FROM Machines M, Systems Sys, Symptoms Sym WHERE M.MachineID = Sys.MachineID AND Sys.SystemID 
=Sym.SystemID AND Sym.SymptomID IN (SELECT DISTINCT SymptomID FROM Tree WHERE SymptomID NOT IN (SELECT DISTINCT SymptomID FROM Tree WHERE LBNodeID = 0 OR RBNodeID = 0)) 

Answer 3

$ Q1是一个MySQL资源变量，而不是字符串或数组。看你从资源要为如何获得特定领域（S）的文档：

http://us2.php.net/mysql_query

http://us2.php.net/manual/en/function.mysql-fetch-array.php