默认情况下，在php中不填充任何数据

Question

Table_sup           |
+-------------------+
| supid=>int        |                
| scompany=>varchar | 
| sstate=>varchar   | 
| scity=>varchar    | 
| scat=>varchar     | 

PHP Code

<?php
    include "db_connect.php";  // including configuration file
?>
     <form name="frmdropdown" method="post" action="sample.php">
     <center>
            <h2 align="center">Select State</h2>
            <strong> Select State : </strong> 
     <select name="getData"> 
            <option value=""> -----------ALL----------- </option>
     <?php
            $dd_res=mysqli_query($con,"Select DISTINCT sstate from sup");   
                while($r=mysqli_fetch_row($dd_res))
                    { echo "<option value='$r[0]'> $r[0] </option>";}
     ?>
    </select>
    <input type="submit" name="Select" value="Select"/> 
    <br><hr>
    <table id="exampleL" class="display table table-striped table-bordered dt-responsive nowrap" cellpadding="1" cellspacing="1" width="" style="font-size:small;">
         <thead>
              <tr>
                   <th style=" background-color:lightblue">Company</th>
                   <th style=" background-color:lightgreen">City</th>
                   <th style=" background-color:lightgreen">State</th>
                   <th style=" background-color:lightgreen">Category</th>
              </tr>
        </thead>
        <tbody>
    <?php
        if($_SERVER['REQUEST_METHOD'] == "POST")
    {
         $des=$_POST["getData"]; 
         if($des=="")  // if ALL is selected in Dropdown box
         { 
             $res=mysqli_query($con,"Select * from sup");
         }
         else
         { 
             $res=mysqli_query($con,"Select * from sup where sstate='".$des."'");
         }
            //echo "<tr><td colspan='5'></td></tr>";
         while($row3=mysqli_fetch_array($res)){
         ?>
               <tr>
                    <td><?php echo $row3['scompany'];?></td>
                    <td><?php echo $row3['scity'];?></td>
                    <td><?php echo $row3['sstate'];?></td>
                    <td><?php echo $row3['scat'];?></td>
               </tr>                     
        <?php
            }
                }
        ?>
        </tbody>
        </table>
        </center>
        </form>

By Default there is no data populated in the table. When I press "select", then all data populate in the table.

What I want: by default, the table populated all data

I have a default table image after running the code.If required I can upload the image

Answer 1

<?php
    include "db_connect.php";  // including configuration file
?>
<form name="frmdropdown" method="post" action="sample.php">
<center>
        <h2 align="center">Select State</h2>
        <strong> Select State : </strong>
<select name="getData">
        <option value=""> -----------ALL----------- </option>
<?php
        $dd_res=mysqli_query($con,"Select DISTINCT sstate from sup");   
            while($r=mysqli_fetch_row($dd_res))
                { echo "<option value='$r[0]'> $r[0] </option>";}
?>
</select>
<input type="submit" name="Select" value="Select"/> 
<br><hr>
<table id="exampleL" class="display table table-striped table-bordered dt-responsive nowrap" cellpadding="1" cellspacing="1" width="" style="font-size:small;">
     <thead>
          <tr>
               <th style=" background-color:lightblue">Company</th>
               <th style=" background-color:lightgreen">City</th>
               <th style=" background-color:lightgreen">State</th>
               <th style=" background-color:lightgreen">Category</th>
          </tr>
    </thead>
    <tbody>
<?php
    $res=mysqli_query($con,"Select * from sup");

    // If select was clicked, then only where condition applies, and so $res will be replaced.
    if(isset($_POST['getData'] ) || !empty($des))
    {
        $des=$_POST["getData"]; 
        $res = mysqli_query($con,"Select * from sup where sstate='".$des."'");         
    }
        //echo "<tr><td colspan='5'></td></tr>";
    while($row3=mysqli_fetch_array($res)){
    ?>
           <tr>
                <td><?php echo $row3['scompany'];?></td>
                <td><?php echo $row3['scity'];?></td>
                <td><?php echo $row3['sstate'];?></td>
                <td><?php echo $row3['scat'];?></td>
           </tr>
    <?php } ?>
    </tbody>
    </table>
    </center>
    </form>