CODEWITHSUNDEEP
phpmysqlmysqli
Tom
Tom

Reputation: 1

Echoing variables from database

I have some PHP code that sets variables from a database. I'll explain, please let me know if it does not make sense.

So, I have a query to select * from the table if class = '$class'. That all works I got it working.

I then set the variables like this $id = $row["id"]; and that all works, in my HTML code I have <p><?php echo $id?></p> and if their class = $class it will display it, however, if it does not meet those requirements the variables are not set, so I get the error Notice: Undefined variable: id in C:\wamp64\www\studentplanner\account\homework.php on line 73.

What I want to do is only output the results in HTML if the requirement was met.

No idea if that makes sense or not!

$sql = "SELECT * FROM homework WHERE class = '$class'";
$result = mysqli_query($conn, $sql);

if (mysqli_num_rows($result) > 0) {
    // output data of each row
    while($row = mysqli_fetch_assoc($result)) {
      $id = $row["id"];
      $teacher_set = $row["teacher_set"];
      $class = $row["class"];
      $name = $row["name"];
      $description = $row["description"];

    }
}


          <p><?php echo $id?></p>
          <p><?php echo $teacher_set?></p>
          <p><?php echo $class?></p>
          <p><?php echo $name?></p>
          <p><?php echo $description?></p>

Upvotes: 0

Views: 35

Answers (2)

Ritesh Khatri
Ritesh Khatri

Reputation: 1301

 $sql = "SELECT * FROM homework WHERE class = '$class'";
 $result = mysqli_query($conn, $sql);

 if (mysqli_num_rows($result) > 0) {
 while($row = mysqli_fetch_assoc($result)) { 
 ?>  
    <p><?php echo $row["id"];?></p>
    <p><?php echo $row["teacher_set"];?></p>
    <p><?php echo $row["class"];?></p>
    <p><?php echo $row["name"];?></p>
    <p><?php echo $row["description"];?></p>
<?php } } ?>

Upvotes: 0

B. Desai
B. Desai

Reputation: 16436

set flag variable before while loop then use that variable to decide whether to print data in html or not

$data_exist = false;
if (mysqli_num_rows($result) > 0) {
    // output data of each row
    $data_exist = true; 
    while($row = mysqli_fetch_assoc($result)) {
      $id = $row["id"];
      $teacher_set = $row["teacher_set"];
      $class = $row["class"];
      $name = $row["name"];
      $description = $row["description"];

    }
}


if($data_exist)
{
?>

          <p><?php echo $id?></p>
          <p><?php echo $teacher_set?></p>
          <p><?php echo $class?></p>
          <p><?php echo $name?></p>
          <p><?php echo $description?></p>
<?php
} 
?>

Upvotes: 1

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