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POMaking a databaseDo() function for hooking PDO queries
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copied!<p>So I started <a href="http://www.phpro.org/tutorials/Introduction-to-PHP-PDO.html#7.1" rel="nofollow">this tutorial</a> as an intro to the PHP PDO. Up until now I've only worked with basic <code>mysql_*</code> type queries. </p> <p>I've noticed that, throughout the tutorial, the <code>connect -> do action -> disconnect</code> pattern is repeated, and only the <code>do action</code> part ever changes. </p> <p>In a real-world setting, would it be a good idea to eliminate repetition by creating a function into which queries can be passed? </p> <p>For example:</p> <h2>a function for handling queries:</h2> <pre><code><?php function databaseDo($action) { $db_hostname = 'localhost'; $db_username = 'root'; $db_password = 'root'; try { // Establish DB connection $dbh = new PDO("mysql:host=$hostname;dbname=mysql", $db_username, $db_password); echo 'Connected to database'; // Do something $action($dbh); // <- here goes whatever action we wish to perform // Close connection $dbh = null; } catch(PDOException $e) { echo $e->getMessage(); } ?> </code></pre> <p>Then, suppose I want to perform the action in the first example of the PDO tutorial, I would set it like this:</p> <pre><code><?php // Define action $insert = function($dbh) { $query = "INSERT INTO animals(animal_type, animal_name) VALUES ('kiwi', 'troy')"; $exec = $dbh->exec($query); echo $exec; }; // Perform action databaseDo($insert); ?> </code></pre> <h2>Scope of $dbh</h2> <p>I am using $dbh as an argument. Is this the proper way of passing a variable to a function like this without making it global? </p>

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