Select individal colums when fetching data from a database - php

Question

I've just started learning PHP so this is quite a struggle for me, any help is appreciated!
So, I've managed to select my database, table and get data from it. But I need to select more data from the older columns.
Here is some of the code:
// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
//execute the SQL query and return records
$result = mysqli_query($conn, "SELECT username FROM interview");
while($rowval = mysqli_fetch_array($result))
{
$username= $rowval['username'];
$username2= $rowval['username'];
$username3= $rowval['username'];
$username4= $rowval['username'];
}
?>
And I am displaying the data in a button, I want $username to display the first column and $username2 to display the second column etc...
I fetch the data using this code:
<?php echo $username; ?>
<?php echo $username2; ?>
<?php echo $username3; ?>
<?php echo $username4; ?>
Thanks!

Answer 1

I would suggest you re-factoring your "while" loop the following way for better scalability:
$usernames=array();
while($rowval = mysqli_fetch_array($result))
{
$usernames[] = $rowval['username'];
}
Then, you'll be able to access usernames like:
echo 'The first user name is: '.$usernames[0];
echo 'The second user name is: '.$usernames[1];
echo 'The third user name is: '.$usernames[2];

Answer 2

My php skills are a bit rusty, so take this with a grain of salt:
At first it is important to get the language right. A database table consists of rows and columns, the columns are the ones you select with the the part after the SELECT statement, if you write SELECT username what you select is the username column.
SELECT username FROM interview;
So if you want to select more columns from your table you have to put them in your SELECT statement. Let's say you want to select the username and the status of the interview, you would need to include the status in your SELECT statement like this:
SELECT username, status from interview;
Then you can access the interview status just like you did it with the username.
$result = mysqli_query($conn, "SELECT username, status from interview;");
while($rowval = mysqli_fetch_array($result))
{
$username= $rowval['username'];
$status = $rowval['status'];
}
Remember that what you get as the $rowVal is just a single row of your table. So if you want to collect all usernames and statuses from your table you have to use a datastructure to collect them.
$queryResult = mysqli_query($conn, "SELECT username, status from interview;");
$result = array();
while($rowval = mysqli_fetch_array($queryResult))
{
$username= $rowval['username'];
$status = $rowval['status'];
// With this action we build an array, that has each row's result as value.
$result[] = array('username' => $username, 'status' => $status);
}
To access the results you can then query the $result array like this:
// The interview status of the first entry in your table
$result[0]['status'];