mysqli_fetch_assoc仅返回数组的第一个元素

I'm working on a project, where the logged in user should be able to post notes on the homepage, and being logged in the certain user's notes should be printed above the new note form. I've written a function for that, where the mysqli_query recognizes all the 6 entries I have, but the mysqli_fetch_assoc prints only the first note out of 6. What could I do wrong? Here is my code:

<?php    
    function find_notes_by_id($user_id) {
    global $connection;
    
    $safe_user_id = mysqli_real_escape_string($connection, $user_id);
    
    $query = 'SELECT content ';
    $query .= 'FROM notes ';
    $query .= 'WHERE user_id = '.$safe_user_id;
    $result = mysqli_query($connection, $query);
 
    //mysqli_result Object ( [current_field] => 0 [field_count] => 1 [lengths] => [num_rows] => 6 [type] => 0 )

    confirm_query($result);

    $row = mysqli_fetch_assoc($result);
    //Array ( [content] => First! ) = it only shows the very first element
    return $row;
}
?>

<?php
$notes_set = find_notes_by_id($userRow['id']);
  foreach($notes_set as $note){
    echo $note;
    echo "<br />";
  }
?>

</div>

1.You need to iterate over your result-set object through while()

2.Save all your data to an array and then return that array to get all records

like below:-

<?php    
  function find_notes_by_id($user_id) {
   global $connection;

    $safe_user_id = mysqli_real_escape_string($connection, $user_id);

    $query = "SELECT `content` FROM `notes` WHERE `user_id` = $safe_user_id";
    $result = mysqli_query($connection, $query);

    confirm_query($result);

    $final_data = array(); // create an array
    while($row = mysqli_fetch_assoc($result)){ // iterate over the result-set object to get all data
        $final_data[] = $row; //assign value to the array
    }
    return $final_data; // return array
  }
?>

Now:-

<?php
$notes_set = find_notes_by_id($userRow['id']);

print_r($notes_set) ; // print result to check array structure so that you can use it correctly in foreach
  foreach($notes_set as $note){
    echo $note['content'];
    echo "<br />";
  }
?>

You can get all results like so:

$arr = $result->fetch_all(MYSQLI_ASSOC);

Or use a while loop:

while($row = $result->fetch_assoc()){
    echo $row['content'] . '<br />';
}

Save data into an array. Use it through foreach or for loop.

$content = [];
while($row = mysqli_fetch_assoc($result)){
   $content[] = $row['content'];
}
return $content;

Need to change the function like this

function find_notes_by_id($user_id) {
    global $connection;

    $safe_user_id = mysqli_real_escape_string($connection, $user_id);

    $query = 'SELECT content ';
    $query .= 'FROM notes ';
    $query .= 'WHERE user_id = '.$safe_user_id;
    $result = mysqli_query($connection, $query);

    //mysqli_result Object ( [current_field] => 0 [field_count] => 1 [lengths] => [num_rows] => 6 [type] => 0 )

    confirm_query($result);
    $row = array();
    while($result1 = mysqli_fetch_assoc($result)){
        //Array ( [content] => First! ) = it only shows the very first element
        $row[] = $result1;
    }
    return $row;
}

You have to iterate over. Problem is with this code

$row = mysqli_fetch_assoc($result);
return $row;

Change that to

$x = array();
while( $row = mysqli_fetch_assoc($result))
{
  $x[] = $row;
}
return $x;

Instead declaring $connection as global pass the $connection variable to the function which would be a efficient way and get the result as array

<?php    
            function find_notes_by_id($user_id,$connection) {

            $safe_user_id = mysqli_real_escape_string($connection, $user_id);

            $query = 'SELECT content ';
            $query .= 'FROM notes ';
            $query .= 'WHERE user_id = '.$safe_user_id;
            $result = mysqli_query($connection, $query);


            confirm_query($result);

         $data = array(); // create an array
       while($row = mysqli_fetch_assoc($result)){ 
         $data[] = $row; 
    }
      return $data;
        }
        ?>

Now call the function like this

 <?php
$notes_set = find_notes_by_id($userRow['id'],$connection);
  foreach($notes_set as $note){
    echo $note['content'];  
  }
?>