douti0687 2015-08-03 07:47
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即使数据库中存在值,也始终执行else子句

    $sql="SELECT * FROM manifest WHERE (awb_no = '$var')";
    $result=mysql_query($sql);  
    if($result==$var)
    {
     echo "tracking id present in the manifest</br>";
    }
     else
    {
      echo "trackingid not present<br>";
      exit(0);
    }

When i retrieve data from database and check it against the data i have entered,even though the data entered is correct and present in the database it executes the else clause.where am i going wrong? please help!

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  • duanji2014 2015-08-03 07:55
    关注

    Try to count the rows from your query so try this:

    $sql = "SELECT * FROM manifest WHERE (awb_no = '$var')";
    $result = mysql_query($sql);  
    if(mysql_num_rows($result) > 0) {
        echo "tracking id present in the manifest</br>";
    } else {
        echo "trackingid not present<br>";
        exit(0);
    }
    

    Btw mysql is depricated so use PDO or mysqli

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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