merge two columns into an array - php

Question

I want to merge two of my columns (yanlis_cevaplar, cevap_icerik) into an array and this code here gives me only one column in array when I print it (yanlis_cevaplar).
How do I fix it?
$cevaplar = "SELECT yanlis_cevaplar FROM cevaplar";
$cevap_sonuc = $conn->query($cevaplar) or die(mysqli_error($conn));
$cevap1 = array(); //create empty array
while ($row = $cevap_sonuc->fetch_array()) { //loop to get all results
$cevap1[] = $row; //grab everything and store inside array
}
$cevaplar2 = "SELECT cevap_icerik FROM cevaplar";
$cevap_sonuc2 = $conn->query($cevaplar) or die(mysqli_error($conn));
$cevap2 = array(); //create empty array
while ($row = $cevap_sonuc2->fetch_array()) { //loop to get all results
$cevap2[] = $row; //grab everything and store inside array
}
$tumcevaplar = array_merge($cevap1, $cevap2);
print_r($tumcevaplar);

Answer 1

Instead of making multiple queries, you can just fetch all the columns you want in one single query:
$cevaplar = "SELECT yanlis_cevaplar, cevap_icerik FROM cevaplar";
$cevap_sonuc = $conn->query($cevaplar) or die(mysqli_error($conn));
// Now you can fetch all the rows straight away without any loop.
// The MYSQLI_ASSOC will return each row as an associative array
$result = $cevap_sonuc->fetch_all(MYSQLI_ASSOC);
print_r($result);
This will result in something like this:
Array
(
[0] => Array
(
[yanlis_cevaplar] => some value
[cevap_icerik] => some value
)
[1] => Array
(
[yanlis_cevaplar] => some value
[cevap_icerik] => some value
)
... and so on ..
)
If this isn't what you want, then you need to show us an example.
I also recommend that you go through some basic SQL tutorials. How SELECT works is SQL 101. Here's one of many guides: https://www.tutorialspoint.com/mysql/mysql-select-query.htm