Subselect instead of view proof-of-concept

subselect.diff

diff --git a/includes/class-campaigns-db.php b/includes/class-campaigns-db.php
index bc572401..ee2e9892 100644
--- a/includes/class-campaigns-db.php
+++ b/includes/class-campaigns-db.php
@@ -27,10 +27,21 @@ class Affiliate_WP_Campaigns_DB extends Affiliate_WP_DB {
 
 		if( defined( 'AFFILIATE_WP_NETWORK_WIDE' ) && AFFILIATE_WP_NETWORK_WIDE ) {
 			// Allows a single visits table for the whole network
-			$this->table_name  = 'affiliate_wp_campaigns';
+			$visits_db  = 'affiliate_wp_visits';
 		} else {
-			$this->table_name  = $wpdb->prefix . 'affiliate_wp_campaigns';
+			$visits_db  = $wpdb->prefix . 'affiliate_wp_visits';
 		}
+
+		$this->table_name = '(
+			SELECT affiliate_id,
+				campaign,
+				COUNT(url) as visits,
+				COUNT(DISTINCT url) as unique_visits,
+				SUM(IF(referral_id<>0,1,0)) as referrals,
+				ROUND((SUM(IF(referral_id<>0,1,0))/COUNT(url)) * 100, 2) as conversion_rate
+			FROM ' . $visits_db . ' GROUP BY affiliate_id, campaign
+			) AS summary_stats';
+
 		$this->primary_key = 'affiliate_id';
 		$this->version     = '1.0';
 	}