diff --git a/src/Core/Cache.php b/src/Core/Cache.php
index 70a9b9f292..5ceb97676f 100644
--- a/src/Core/Cache.php
+++ b/src/Core/Cache.php
@@ -76,6 +76,7 @@ class Cache
 				$seconds = 300;
 				break;
 			case CACHE_MINUTE:
+			default:
 				$seconds = 60;
 				break;
 		}
diff --git a/src/Core/Worker.php b/src/Core/Worker.php
index 140d0e014d..f5979a82ab 100644
--- a/src/Core/Worker.php
+++ b/src/Core/Worker.php
@@ -389,9 +389,10 @@ class Worker
 		if (Config::get("system", "profiler")) {
 			$duration = microtime(true)-$a->performance["start"];
 
+			$o = '';
 			if (Config::get("rendertime", "callstack")) {
 				if (isset($a->callstack["database"])) {
-					$o = "\nDatabase Read:\n";
+					$o .= "\nDatabase Read:\n";
 					foreach ($a->callstack["database"] as $func => $time) {
 						$time = round($time, 3);
 						if ($time > 0) {
@@ -417,8 +418,6 @@ class Worker
 						}
 					}
 				}
-			} else {
-				$o = '';
 			}
 
 			logger(
@@ -564,6 +563,7 @@ class Worker
 					// We killed the stale process.
 					// To avoid a blocking situation we reschedule the process at the beginning of the queue.
 					// Additionally we are lowering the priority. (But not PRIORITY_CRITICAL)
+					$new_priority = $entry["priority"];
 					if ($entry["priority"] == PRIORITY_HIGH) {
 						$new_priority = PRIORITY_MEDIUM;
 					} elseif ($entry["priority"] == PRIORITY_MEDIUM) {
@@ -768,7 +768,7 @@ class Worker
 		$limit = min($queue_length, ceil($slope * pow($jobs, $exponent)));
 
 		logger('Total: '.$jobs.' - Maximum: '.$queue_length.' - jobs per queue: '.$limit, LOGGER_DEBUG);
-
+		$ids = [];
 		if (self::passingSlow($highest_priority)) {
 			// Are there waiting processes with a higher priority than the currently highest?
 			$result = dba::select(
diff --git a/src/Database/DBStructure.php b/src/Database/DBStructure.php
index 9a1c8a2d52..12cf71861d 100644
--- a/src/Database/DBStructure.php
+++ b/src/Database/DBStructure.php
@@ -244,19 +244,18 @@ class DBStructure
 
 		// Compare it
 		foreach ($definition AS $name => $structure) {
-			$is_new_table = False;
+			$is_new_table = false;
 			$group_by = "";
 			$sql3 = "";
+			$is_unique = false;
+			$temp_name = $name;
 			if (!isset($database[$name])) {
 				$r = self::createTable($name, $structure["fields"], $verbose, $action, $structure['indexes']);
 				if (!DBM::is_result($r)) {
 					$errors .= self::printUpdateError($name);
 				}
-				$is_new_table = True;
+				$is_new_table = true;
 			} else {
-				$is_unique = false;
-				$temp_name = $name;
-
 				foreach ($structure["indexes"] AS $indexname => $fieldnames) {
 					if (isset($database[$name]["indexes"][$indexname])) {
 						$current_index_definition = implode(",",$database[$name]["indexes"][$indexname]);
@@ -463,7 +462,7 @@ class DBStructure
 						if ($ignore != "") {
 							dba::e("SET session old_alter_table=1;");
 						} else {
-							dba::e("DROP TABLE IF EXISTS `".$temp_name."`;");
+							$r = dba::e("DROP TABLE IF EXISTS `".$temp_name."`;");
 							if (!DBM::is_result($r)) {
 								$errors .= self::printUpdateError($sql3);
 								return $errors;
diff --git a/src/Model/Contact.php b/src/Model/Contact.php
index 1d31c6cb5b..7415bac0a9 100644
--- a/src/Model/Contact.php
+++ b/src/Model/Contact.php
@@ -1365,6 +1365,7 @@ class Contact extends BaseObject
 		$url = notags(trim($datarray['author-link']));
 		$name = notags(trim($datarray['author-name']));
 		$photo = notags(trim($datarray['author-avatar']));
+		$nick = '';
 
 		if (is_object($item)) {
 			$rawtag = $item->get_item_tags(NAMESPACE_ACTIVITY,'actor');
@@ -1398,20 +1399,16 @@ class Contact extends BaseObject
 				intval(CONTACT_IS_FOLLOWER)
 			);
 
-			$r = q("SELECT `id`, `network` FROM `contact` WHERE `uid` = %d AND `url` = '%s' AND `pending` = 1 LIMIT 1",
-					intval($importer['uid']),
-					dbesc($url)
-			);
-			if (DBM::is_result($r)) {
-				$contact_record = $r[0];
-				Contact::updateAvatar($photo, $importer["uid"], $contact_record["id"], true);
-			}
+			$contact_record = [
+				'id' => dba::lastInsertId(),
+				'network' => NETWORK_OSTATUS
+			];
+			Contact::updateAvatar($photo, $importer["uid"], $contact_record["id"], true);
 
 			/// @TODO Encapsulate this into a function/method
-			$r = q("SELECT * FROM `user` WHERE `uid` = %d LIMIT 1",
-				intval($importer['uid'])
-			);
-			if (DBM::is_result($r) && !in_array($r[0]['page-flags'], [PAGE_SOAPBOX, PAGE_FREELOVE, PAGE_COMMUNITY])) {
+			$fields = ['uid', 'username', 'email', 'page-flags', 'notify-flags', 'language'];
+			$user = dba::selectFirst('user', $fields, ['uid' => $importer['uid']]);
+			if (DBM::is_result($user) && !in_array($user['page-flags'], [PAGE_SOAPBOX, PAGE_FREELOVE, PAGE_COMMUNITY])) {
 				// create notification
 				$hash = random_string();
 
@@ -1423,16 +1420,16 @@ class Contact extends BaseObject
 
 				Group::addMember(User::getDefaultGroup($importer['uid'], $contact_record["network"]), $contact_record['id']);
 
-				if (($r[0]['notify-flags'] & NOTIFY_INTRO) &&
-					in_array($r[0]['page-flags'], [PAGE_NORMAL])) {
+				if (($user['notify-flags'] & NOTIFY_INTRO) &&
+					in_array($user['page-flags'], [PAGE_NORMAL])) {
 
 					notification([
 						'type'         => NOTIFY_INTRO,
-						'notify_flags' => $r[0]['notify-flags'],
-						'language'     => $r[0]['language'],
-						'to_name'      => $r[0]['username'],
-						'to_email'     => $r[0]['email'],
-						'uid'          => $r[0]['uid'],
+						'notify_flags' => $user['notify-flags'],
+						'language'     => $user['language'],
+						'to_name'      => $user['username'],
+						'to_email'     => $user['email'],
+						'uid'          => $user['uid'],
 						'link'		   => System::baseUrl() . '/notifications/intro',
 						'source_name'  => ((strlen(stripslashes($contact_record['name']))) ? stripslashes($contact_record['name']) : L10n::t('[Name Withheld]')),
 						'source_link'  => $contact_record['url'],
@@ -1442,13 +1439,12 @@ class Contact extends BaseObject
 					]);
 
 				}
-			} elseif (DBM::is_result($r) && in_array($r[0]['page-flags'], [PAGE_SOAPBOX, PAGE_FREELOVE, PAGE_COMMUNITY])) {
+			} elseif (DBM::is_result($user) && in_array($user['page-flags'], [PAGE_SOAPBOX, PAGE_FREELOVE, PAGE_COMMUNITY])) {
 				q("UPDATE `contact` SET `pending` = 0 WHERE `uid` = %d AND `url` = '%s' AND `pending` LIMIT 1",
 						intval($importer['uid']),
 						dbesc($url)
 				);
 			}
-
 		}
 	}
 
diff --git a/src/Model/GContact.php b/src/Model/GContact.php
index e543e4baeb..7b14b2cdc4 100644
--- a/src/Model/GContact.php
+++ b/src/Model/GContact.php
@@ -665,6 +665,8 @@ class GContact
 	{
 		$gcontact_id = 0;
 		$doprobing = false;
+		$last_failure_str = '';
+		$last_contact_str = '';
 
 		if (in_array($contact["network"], [NETWORK_PHANTOM])) {
 			logger("Invalid network for contact url ".$contact["url"]." - Called by: ".System::callstack(), LOGGER_DEBUG);
diff --git a/src/Model/Item.php b/src/Model/Item.php
index fae3394bc3..30fc4ecef9 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -251,9 +251,8 @@ class Item extends BaseObject
 			$arr['network'] = trim(defaults($arr, 'network', NETWORK_PHANTOM));
 		}
 
-		if ($notify) {
-			$guid_prefix = "";
-		} elseif ((trim($arr['guid']) == "") && (trim($arr['plink']) != "")) {
+		$guid_prefix = '';
+		if ((trim($arr['guid']) == "") && (trim($arr['plink']) != "")) {
 			$arr['guid'] = self::guidFromUri($arr['plink']);
 		} elseif ((trim($arr['guid']) == "") && (trim($arr['uri']) != "")) {
 			$arr['guid'] = self::guidFromUri($arr['uri']);
@@ -521,6 +520,11 @@ class Item extends BaseObject
 
 		$arr['thr-parent'] = $arr['parent-uri'];
 
+		$notify_type = '';
+		$allow_cid = '';
+		$allow_gid = '';
+		$deny_cid  = '';
+		$deny_gid  = '';
 		if ($arr['parent-uri'] === $arr['uri']) {
 			$parent_id = 0;
 			$parent_deleted = 0;
diff --git a/src/Model/Mail.php b/src/Model/Mail.php
index b2e9e1a487..81494e7ebb 100644
--- a/src/Model/Mail.php
+++ b/src/Model/Mail.php
@@ -67,6 +67,7 @@ class Mail
 			}
 		}
 
+		$convuri = '';
 		if (!$convid) {
 			// create a new conversation
 			$recip_host = substr($contact['url'], strpos($contact['url'], '://') + 3);
diff --git a/src/Model/Photo.php b/src/Model/Photo.php
index cf31849c8d..e4e609155c 100644
--- a/src/Model/Photo.php
+++ b/src/Model/Photo.php
@@ -91,6 +91,9 @@ class Photo
 	 */
 	public static function importProfilePhoto($image_url, $uid, $cid, $quit_on_error = false)
 	{
+		$thumb = '';
+		$micro = '';
+
 		$photo = dba::selectFirst(
 			'photo', ['resource-id'], ['uid' => $uid, 'contact-id' => $cid, 'scale' => 4, 'album' => 'Contact Photos']
 		);
diff --git a/src/Model/Profile.php b/src/Model/Profile.php
index f79b89014b..f31c83c857 100644
--- a/src/Model/Profile.php
+++ b/src/Model/Profile.php
@@ -565,8 +565,10 @@ class Profile
 				Cache::set($cachekey, $r, CACHE_HOUR);
 			}
 		}
+
+		$total = 0;
+		$classtoday = '';
 		if (DBM::is_result($r)) {
-			$total = 0;
 			$now = strtotime('now');
 			$cids = [];
 
diff --git a/src/Model/User.php b/src/Model/User.php
index f92611cb23..eacd4ec33c 100644
--- a/src/Model/User.php
+++ b/src/Model/User.php
@@ -157,6 +157,8 @@ class User
 	 */
 	private static function getAuthenticationInfo($user_info)
 	{
+		$user = null;
+
 		if (is_object($user_info) || is_array($user_info)) {
 			if (is_object($user_info)) {
 				$user = (array) $user_info;
diff --git a/src/Network/Probe.php b/src/Network/Probe.php
index dac01b1e53..d14c623e86 100644
--- a/src/Network/Probe.php
+++ b/src/Network/Probe.php
@@ -1542,29 +1542,31 @@ class Probe
 			return false;
 		}
 
-		if ($uid != 0) {
-			$x = q("SELECT `prvkey` FROM `user` WHERE `uid` = %d LIMIT 1", intval($uid));
+		if ($uid == 0) {
+			return false;
+		}
 
-			$r = q("SELECT * FROM `mailacct` WHERE `uid` = %d AND `server` != '' LIMIT 1", intval($uid));
+		$x = q("SELECT `prvkey` FROM `user` WHERE `uid` = %d LIMIT 1", intval($uid));
 
-			if (DBM::is_result($x) && DBM::is_result($r)) {
-				$mailbox = Email::constructMailboxName($r[0]);
-				$password = '';
-				openssl_private_decrypt(hex2bin($r[0]['pass']), $password, $x[0]['prvkey']);
-				$mbox = Email::connect($mailbox, $r[0]['user'], $password);
-				if (!mbox) {
-					return false;
-				}
-			}
+		$r = q("SELECT * FROM `mailacct` WHERE `uid` = %d AND `server` != '' LIMIT 1", intval($uid));
 
-			$msgs = Email::poll($mbox, $uri);
-			logger('searching '.$uri.', '.count($msgs).' messages found.', LOGGER_DEBUG);
-
-			if (!count($msgs)) {
+		if (DBM::is_result($x) && DBM::is_result($r)) {
+			$mailbox = Email::constructMailboxName($r[0]);
+			$password = '';
+			openssl_private_decrypt(hex2bin($r[0]['pass']), $password, $x[0]['prvkey']);
+			$mbox = Email::connect($mailbox, $r[0]['user'], $password);
+			if (!$mbox) {
 				return false;
 			}
 		}
 
+		$msgs = Email::poll($mbox, $uri);
+		logger('searching '.$uri.', '.count($msgs).' messages found.', LOGGER_DEBUG);
+
+		if (!count($msgs)) {
+			return false;
+		}
+
 		$phost = substr($uri, strpos($uri, '@') + 1);
 
 		$data = [];
diff --git a/src/Util/ParseUrl.php b/src/Util/ParseUrl.php
index e8094959d6..b267c61086 100644
--- a/src/Util/ParseUrl.php
+++ b/src/Util/ParseUrl.php
@@ -50,19 +50,11 @@ class ParseUrl
 			return false;
 		}
 
-		$r = q(
-			"SELECT * FROM `parsed_url` WHERE `url` = '%s' AND `guessing` = %d AND `oembed` = %d",
-			dbesc(normalise_link($url)),
-			intval(!$no_guessing),
-			intval($do_oembed)
+		$parsed_url = dba::selectFirst('parsed_url', ['content'],
+			['url' => normalise_link($url), 'guessing' => !$no_guessing, 'oembed' => $do_oembed]
 		);
-
-		if ($r) {
-			$data = $r[0]["content"];
-		}
-
-		if (!is_null($data)) {
-			$data = unserialize($data);
+		if (!empty($parsed_url['content'])) {
+			$data = unserialize($parsed_url['content']);
 			return $data;
 		}
 
diff --git a/src/Util/XML.php b/src/Util/XML.php
index d8c5e03239..8dc5403243 100644
--- a/src/Util/XML.php
+++ b/src/Util/XML.php
@@ -52,6 +52,7 @@ class XML
 			}
 		}
 
+		$element = null;
 		foreach ($array as $key => $value) {
 			if (!isset($element) && isset($xml)) {
 				$element = $xml;
@@ -185,12 +186,13 @@ class XML
 			return(null);
 		}
 
+		$xml_element_copy = '';
 		if (!is_string($xml_element)
 			&& !is_array($xml_element)
 			&& (get_class($xml_element) == 'SimpleXMLElement')
 		) {
-				$xml_element_copy = $xml_element;
-				$xml_element = get_object_vars($xml_element);
+			$xml_element_copy = $xml_element;
+			$xml_element = get_object_vars($xml_element);
 		}
 
 		if (is_array($xml_element)) {
diff --git a/src/Worker/Delivery.php b/src/Worker/Delivery.php
index 2b9a00176e..dbc0bdb5d0 100644
--- a/src/Worker/Delivery.php
+++ b/src/Worker/Delivery.php
@@ -34,11 +34,12 @@ class Delivery {
 		$relocate = false;
 		$top_level = false;
 		$recipients = [];
-		$url_recipients = [];
 		$followup = false;
 
 		$normal_mode = true;
 
+		$item = null;
+
 		$recipients[] = $contact_id;
 
 		if ($cmd === 'mail') {
@@ -182,16 +183,14 @@ class Delivery {
 
 		}
 
-		$r = q("SELECT * FROM `contact` WHERE `id` = %d AND `blocked` = 0 AND `pending` = 0",
-			intval($contact_id)
+		// We don't deliver our items to blocked or pending contacts, and not to ourselves either
+		$contact = dba::selectFirst('contact', [],
+			['id' => $contact_id, 'blocked' => false, 'pending' => false, 'self' => false]
 		);
-
-		if (DBM::is_result($r)) {
-			$contact = $r[0];
-		}
-		if ($contact['self']) {
+		if (!DBM::is_result($contact)) {
 			return;
 		}
+
 		$deliver_status = 0;
 
 		// Transmit via Diaspora if not possible via Friendica
@@ -207,7 +206,7 @@ class Delivery {
 				logger('notifier: '.$target_item["guid"].' dfrndelivery: '.$contact['name']);
 
 				if ($mail) {
-					$item['body'] = Item::fixPrivatePhotos($item['body'],$owner['uid'],null,$message[0]['contact-id']);
+					$item['body'] = Item::fixPrivatePhotos($item['body'], $owner['uid'], null, $item['contact-id']);
 					$atom = DFRN::mail($item, $owner);
 				} elseif ($fsuggest) {
 					$atom = DFRN::fsuggest($item, $owner);
diff --git a/src/Worker/DiscoverPoCo.php b/src/Worker/DiscoverPoCo.php
index a5e1e6ee2d..a82fa12087 100644
--- a/src/Worker/DiscoverPoCo.php
+++ b/src/Worker/DiscoverPoCo.php
@@ -30,6 +30,8 @@ class DiscoverPoCo {
 		- check_profile: Update remote profile data
 		*/
 
+		$search = "";
+		$mode = 0;
 		if ($command == "dirsearch") {
 			$search = urldecode($param1);
 			$mode = 1;
@@ -47,10 +49,7 @@ class DiscoverPoCo {
 			$mode = 7;
 		} elseif ($command == "check_profile") {
 			$mode = 8;
-		} elseif ($command == '') {
-			$search = "";
-			$mode = 0;
-		} else {
+		} elseif ($command !== "") {
 			logger("Unknown or missing parameter ".$command."\n");
 			return;
 		}
diff --git a/src/Worker/Notifier.php b/src/Worker/Notifier.php
index b050c5e2f5..f22549c2b8 100644
--- a/src/Worker/Notifier.php
+++ b/src/Worker/Notifier.php
@@ -67,6 +67,7 @@ class Notifier {
 		$url_recipients = [];
 
 		$normal_mode = true;
+		$recipients_relocate = [];
 
 		if ($cmd === 'mail') {
 			$normal_mode = false;
@@ -178,6 +179,10 @@ class Notifier {
 		// fill this in with a single salmon slap if applicable
 		$slap = '';
 
+		$followup = false;
+		$recipients_followup = [];
+		$conversants = [];
+		$sql_extra = '';
 		if (! ($mail || $fsuggest || $relocate)) {
 
 			$slap = OStatus::salmon($target_item, $owner);
@@ -321,8 +326,6 @@ class Notifier {
 					Worker::add($a->queue['priority'], 'Notifier', 'uplink', $item_id);
 				}
 
-				$conversants = [];
-
 				foreach ($items as $item) {
 					$recipients[] = $item['contact-id'];
 					$conversants[] = $item['contact-id'];
@@ -519,7 +522,7 @@ class Notifier {
 					// except for Diaspora batch jobs
 					// Don't deliver to folks who have already been delivered to
 
-					if (($rr['network'] !== NETWORK_DIASPORA) && (in_array($rr['id'],$conversants))) {
+					if (($rr['network'] !== NETWORK_DIASPORA) && (in_array($rr['id'], $conversants))) {
 						logger('notifier: already delivered id=' . $rr['id']);
 						continue;
 					}
diff --git a/src/Worker/OnePoll.php b/src/Worker/OnePoll.php
index 377bda85f4..2594f4ec1d 100644
--- a/src/Worker/OnePoll.php
+++ b/src/Worker/OnePoll.php
@@ -153,6 +153,7 @@ class OnePoll
 		}
 
 		$importer = $r[0];
+		$url = '';
 
 		logger("poll: ({$contact['network']}-{$contact['id']}) IMPORTER: {$importer['name']}, CONTACT: {$contact['name']}");