Lots of foreach is it ok?

Question

PHP

In general, as I understand it, you need to make as few queries to the database as possible, and I decided to send a request to the database once and write the answer to array 1, and only then from array 1 everything you need to get. And now I have such a question, I made the following code (Ps I immediately say to the name of the variables, do not pay attention, I'm only learning and this is for the test):

$catalog = 1; // Для теста 

$qa_products = $link->query('SELECT * FROM `products`');
  $array_products = array();
  while($w_products = $qa_products->fetch(PDO::FETCH_ASSOC)) {
    $array_products[] = $w_products;
  }

// В другом месте, код ( Нужно сделать поиск id каталога по массиву 1, если такой каталог найден, то он записывается в другой массив 2, потом массив 2 проверятся на кол-во строк, если их 0, то пишет что аккаунтов не найдено, если их >=1, то через foreach все они выводятся):

$get_catalog_1 = array();

              foreach($array_products as $for_products_1) {
                if($for_products_1['catalog_id'] == $catalog) {
                  $get_catalog_1[] = $for_products_1;
                }
              }

              if(count($get_catalog_1) >= 1) {
                foreach($get_catalog_1 as $set_catalog_1): ?>
                  <p><?php echo $set_catalog_1['title']; ?></p>
                <?php endforeach;
              } else {
                ?>
                  <p>В данной категории нет аккаунтов</p>
                <?php
              }

If this code is run, then everything works. But is it okay to do it this way? Is it normal that I use arrays and foreach so much? And if not right, how would it be better to do it?

Answer 1

SELECT * FROM `products` WHERE catalog_id = 1
This query will minify the code.

Answer 2

if I understand correctly, you need an array_filter so as not to go over extra elements

Answer 3

Think:
much better than what you wrote. The code will be 3-4 times shorter and clearer.
In terms of speed:
- on a small table, the difference tends to zero
- on a millionth, MySQL with indexes is better.

Answer 4

1. Search logic is better to take out in sql
2. Where it is possible to use built-in functions - it is better to use built-in functions.
3. A cycle to output something is normal. It is bad to make queries in sql in a loop