爆炸并检查是否存在

this is MySQL table structure:

TABLE: products

|----------------------------------------------|
|   id    |             product_ids            |
|   1     |              51                    |
|   2     |              616,2,38              |
|   3     |              (NULL)                |
|   4     |              426,605,604           |
|----------------------------------------------|

What im looking is a way for the code to check if the id 605 exists in product_ids row, and if it does to replace for another ID:

any idea how can i accomplish this?

I was thinking of a sql QUERY...

To find out if it contains '605':

SELECT id, product_ids FROM products 
where product_ids REGEXP '^.*[^\d]605(?!\d).*$'

Comment: this is, by the way, a very good example why we shouldn't use multiple values in the same field!

Now once you have it - you can do whatever you want, you can play with it:

$new_product_ids = preg_replace('/^(.*[^\d])(605)(?!\d)(.*)$/','${1}new_id${3}',$row1['product_ids']);

and update the row:

update products set product_ids = '$new_product_ids' where id = $id

while ($row1 = mysql_fetch_array($r1, MYSQL_ASSOC)) {   

    if($row1['product_ids']){
      $val_changed = false;
      $prod_ids = $row1['product_ids'];
      $ids = explode(',', $prod_ids);
      for($i = 0; $i < count($ids); $i++) {
        if($ids[$i] === '605') {
          $ids[$i] = $new_id;
          $val_changed = true;
        }
      }

      if($val_changed) {
        $prod_ids = implode(',', $ids);
        //update db with new value $prod_ids
      }
    }
}

To get only records that have the id you're looking for, and use preg_replace to change the value, and update the table with the new value

$new_id = '999';
$new_val = preg_replace('/,605,/', $new_id, $row1['product_ids']);

Query with Regex (Fancy!):

SELECT * FROM products WHERE product_ids REGEXP '^[^0-9]605[^0-9]$';

Script to modify data:

while( $row1 = mysql_fetch_array( $r1, MYSQL_ASSOC ) )
{   
    $product_ids = explode( ',', $row1['product_ids'] );

    if( ( $key = array_search( '605', $product_ids ) ) !== FALSE )
    {
        $product_ids[$key] = $new_id_number;

        $product_ids = implode( ',', $product_ids );

        // Enter Code to Update Table Here
    }
}

$sql = "SELECT * FROM products"; 
$r1=$con->execute_query($sql);

while ($row1 = mysql_fetch_array($r1, MYSQL_ASSOC)) {       
  if($row1['product_ids']) {
    $data = preg_split('/,/', $row1['product_ids']);
     if(is_array($data)) {
       foreach($data as $key => $value) {
           if($value == 605) {
               echo $value;
           }
       }
     }
  }   
}

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