Add data to a Custom WordPress table

gistfile1.php

<?php

/* create a function to get the values from this page load */
function wpct_track_content() {

	/* call the global post variable to gain access to post data */
	global $post;
	
	/* setup an array to store all our values */
	$wpct_post_values = array();
	
	/* collect the information we need, starting with post id */
	$wpct_post_id = $post->ID;
	
	/* get the current logged in user */
	$wpct_current_user = wp_get_current_user();
	
	/* get the logged in user ID */
	$wpct_current_user_id = $wpct_current_user->ID;
	
	/* get the logged in users username */
	$wpct_current_user_name = $wpct_current_user->user_login;
	
	/* get the current date and time */
	$wcpt_date = date( 'Y-m-d H:i:s' );
	
	/* get the users ip address */
	$wpct_ip = $_SERVER[ 'REMOTE_ADDR' ];
	
	/* add all collected values to the array */
	$wpct_post_values[ 'wpct_post_id' ] = $wpct_post_id;
	$wpct_post_values[ 'wpct_user_id' ] = $wpct_current_user_id;
	$wpct_post_values[ 'wpct_username' ] = $wpct_current_user_name;
	$wpct_post_values[ 'wpct_date' ] = $wcpt_date;
	$wpct_post_values[ 'wpct_ip' ] = $wpct_ip;
	
	/* lets check this is a singular page view, we are not tracking other page views */
	if( is_singular() ) {

	  /* record a page load in the table writing entry to database */
	  global $wpdb;
	
  	/* get the table name */
	  $wpct_tablename = $wpdb->prefix . "wpct";
	
	  /* insert the values into a row in the custom table */
	  $wpdb->insert(
	    $wpct_tablename, // name of our custom table
  	  $wpct_post_values // array of values to write
	  );

	}

}
	
/* hook our content values function into wordpress */
add_action( 'wp', 'wpct_track_content' );

?>