PHP explode and MySQL query to search in multiple columns
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I have a form where I want a user to enter one or more words. These words should then match mutiple columns in a MySQL database.

I have started to build some code but I'm stuck.

    <?php
      $term = $_SESSION['session_searchstring']; //Let's say that session is John Doe
      $searchterm = explode(' ',$term);

      $searchFieldName = "name";
      $searchCondition = "$searchFieldName LIKE '%" . implode("%' OR $searchFieldName LIKE '%", $searchterm) . "%'";

      $sql = "SELECT * FROM students WHERE $searchCondition;";

      echo $sql; //Echo to test what mysql_query would look like

    ?>

The above code will output:

    SELECT * FROM students WHERE name LIKE '%John%' OR name LIKE '%Doe%'; 

The problem is that I want to search in multiple columns (`$searchFieldName`). I have for example 

    customer_firstname
    customer_lastname

And I want to match my searchstring against the content of both columns.. How would I continue?