doushi9729 2010-11-30 10:02
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max SQL函数问题

I have this code in PHP

$max="SELECT MAX(num) FROM info";
$maxquery= mysql_query($max) or die (died);
while($row = mysql_fetch_array($maxquery)){
    echo "The max num is ". $row['num']."this is it";
}
$maxnum= mysql_fetch_array($maxquery);
echo "<br>".$maxnum."hh";

then the output be:

The max num is this is it

hh


Why didn't the query get the max number?

The table is called info and it has these fields, ID, num, title, description, and answer.


After editing:

I tried my query in MySQL and it works fine!

"SELECT MAX(num) FROM info"

and this is my complete code if it can help:

<?php
    $answer=$_GET["answerbox"];
    $ID=$_GET["TheID"];

    $host="localhost";
    $username="root";
    $password="";
    $db_name="game";
    mysql_connect("$host","$username","$password")or die("cannot connect");
    mysql_select_db("$db_name")or die("cannot select DB");

    $max="SELECT MAX(num) FROM info";
    $maxquery= mysql_query($max) or die (died);
    while($row = mysql_fetch_array($maxquery)) {
        echo "The max num is ". $row['num']."this is it";
    }

    $maxnum= mysql_fetch_array($maxquery);
    $sql="SELECT * FROM info  WHERE ID=".$ID;
    $query = mysql_query($sql) or die(errorquery);
    $row = mysql_fetch_array($query);
    $trueanswer = $row['Answer'];
    $num=$row['num'];
    if ($num<$maxnum)
    {
        $numto= $num +1 ;
        echo "<br>".$maxnum."hh";
    }
?>
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6条回答 默认 最新

  • dousuochu7291 2010-11-30 10:05
    关注

    Then the code will be

    $max="SELECT MAX(num) as num FROM info";
    $maxquery= mysql_query($max) or die (died);
    while($row = mysql_fetch_assoc($maxquery)) {
        echo "The max num is ". $row['num']."this is it";
    }
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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