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好的，所以这听起来有点奇怪，而且可能过于复杂。这是情况。我 2 组 3 个查询。我将尝试做一个简单的例子来准确解释我想要做什么：

查询：

//First set of queries
$query1 = "SELECT Name, Date FROM Table1";
$query2 = "SELECT Type, Place, Location FROM Table2";
$query3 = "SELECT One FROM Table3";

//Second set of queries
$query4 = "SELECT Name, Date FROM Table1 WHERE ID=1";
$query5 = "SELECT Type, Place, Location FROM Table2 WHERE ID=1";
$query6 = "SELECT One FROM Table3 WHERE ID=1";

当我告诉你我不能组合这两组查询时，你只需要相信我。这些是过度简化的选择语句，以了解我正在尝试做的事情。

所以这是我的php代码：

//Set 1
$data1 = mysql_query($query1) or die(mysql_error());
$data2 = mysql_query($query2) or die(mysql_error());
$data3 = mysql_query($query3) or die(mysql_error());
while ($line1 = mysql_fetch_array($data1, MYSQL_ASSOC) &&
        $line2 = mysql_fetch_array($data2, MYSQL_ASSOC)) {
    while ($line3 = mysql_fetch_array($data3, MYSQL_ASSOC)) {
        //COMBINE $line1, line2, line3 into a single $lineSet1 -- HOW DO I DO THIS?
    }
}

//Set 2
$data4 = mysql_query($query4) or die(mysql_error());
$data5 = mysql_query($query5) or die(mysql_error());
$data6 = mysql_query($query6) or die(mysql_error());
while ($line4 = mysql_fetch_array($data4, MYSQL_ASSOC) &&
        $line5 = mysql_fetch_array($data5, MYSQL_ASSOC)) {
    while ($line6 = mysql_fetch_array($data6, MYSQL_ASSOC)) {
        //COMBINE $line4, line5, line6 into a single $lineSet2 -- HOW DO I DO THIS?
    }
}

//Append $lineset1 and $lineset2 so I have 1 resultset $results
$result = array_merge($lineSet1, $lineSet2);
//So now I can pass this $result array into my array2csv function that takes a multidimensional array:
function array2csv(array &$array)
{
   if (count($array) == 0) {
     return null;
   }
   ob_start();
   $df = fopen("exportedLeads{$_SESSION['id']}.csv", 'w');
   fputcsv($df, array_keys(reset($array)));
   foreach ($array as $row) {
      fputcsv($df, $row);
   }
   fclose($df);
   return ob_get_clean();
}

我知道这看起来很复杂，但我很困惑，而且不擅长 php。任何帮助，将不胜感激。谢谢！

TABLE1:

ID | Name | Date

TABLE2:

ID | Table1_ID | Type | Place | Location

TABLE3:

ID | Table1_ID | One

编辑：我一直在阅读JOIN声明。这可能是一个案例吗？

4

2 回答 2

1

You can resume both of your sets into a single query like using JOIN assuming your ID's match.

First set into 1 query:

SELECT t1.Name, t1.Date, t2.Type, t2.Place, t3.One FROM Table1 t1
  JOIN Table2 t2
    ON t2.Table1_ID = t1.ID
  JOIN Table3 t3
    ON t3.Table1_ID = t1.ID

Second set into 1 query:

SELECT t1.Name, t1.Date, t2.Type, t2.Place, T2.Location, t3.One
  FROM Table1 t1
  JOIN Table2 t2
    ON t2.Table1_ID = t1.ID
  JOIN Table3 t3
    ON t3.Table1_ID = t1.ID
 WHERE t1.ID = 1
于 2013-08-13T20:02:19.940 回答
0

假设您的三个查询都返回相同数量的行，您可以滥用赋值运算符：

while(($row1 = mysql_fetch($result1))
   && ($row2 = mysql_fetch($result2))
   && ($row3 = mysql_fetch($result3))) {

to fetch from all three result sets in parallel. The downside is that if your result sets are different lengths, you'll only fetch as many records as there are in the SHORTEST result set. e.g. as soon as any of those fetch calls returns false, the entire while aborts, even if there's still data in the other two results.

于 2013-08-13T19:49:12.143 回答