diff --git a/boot.php b/boot.php
index ac21d108a..864e7804c 100644
--- a/boot.php
+++ b/boot.php
@@ -41,7 +41,7 @@ define('FRIENDICA_PLATFORM',     'Friendica');
 define('FRIENDICA_CODENAME',     'The Tazmans Flax-lily');
 define('FRIENDICA_VERSION',      '2018.08-dev');
 define('DFRN_PROTOCOL_VERSION',  '2.23');
-define('DB_UPDATE_VERSION',      1271);
+define('DB_UPDATE_VERSION',      1272);
 define('NEW_UPDATE_ROUTINE_VERSION', 1170);
 
 /**
@@ -451,8 +451,9 @@ define('ACTIVITY_OBJ_QUESTION', 'http://activityschema.org/object/question');
  * @{
  */
 define('GRAVITY_PARENT',       0);
-define('GRAVITY_LIKE',         3);
+define('GRAVITY_ACTIVITY',     3);
 define('GRAVITY_COMMENT',      6);
+define('GRAVITY_UNKNOWN',      9);
 /* @}*/
 
 /**
diff --git a/database.sql b/database.sql
index 9711ace80..1a08a5ba9 100644
--- a/database.sql
+++ b/database.sql
@@ -1,6 +1,6 @@
 -- ------------------------------------------
 -- Friendica 2018.08-dev (The Tazmans Flax-lily)
--- DB_UPDATE_VERSION 1271
+-- DB_UPDATE_VERSION 1272
 -- ------------------------------------------
 
 
@@ -565,6 +565,7 @@ CREATE TABLE IF NOT EXISTS `item-content` (
 	`target-type` varchar(100) NOT NULL DEFAULT '' COMMENT 'ActivityStreams target type if applicable (URI)',
 	`target` text COMMENT 'JSON encoded target structure if used',
 	`plink` varchar(255) NOT NULL DEFAULT '' COMMENT 'permalink or URL to a displayable copy of the message at its source',
+	`verb` varchar(100) NOT NULL DEFAULT '' COMMENT 'ActivityStreams verb',
 	 PRIMARY KEY(`id`),
 	 UNIQUE INDEX `uri-plink-hash` (`uri-plink-hash`),
 	 INDEX `uri` (`uri`(191))
diff --git a/include/api.php b/include/api.php
index 819d2c75a..32fe6c651 100644
--- a/include/api.php
+++ b/include/api.php
@@ -1270,8 +1270,8 @@ function api_status_show($type)
 	}
 
 	// get last public wall message
-	$condition = ["`owner-id` = ? AND `uid` = ? AND `type` != 'activity' ".$privacy_sql,
-		$user_info['pid'], api_user()];
+	$condition = ['owner-id' => $user_info['pid'], 'uid' => api_user(),
+		'gravity' => [GRAVITY_PARENT, GRAVITY_COMMENT]];
 	$lastwall = dba::selectFirst('item', [], $condition, ['order' => ['id' => true]]);
 
 	if (DBM::is_result($lastwall)) {
@@ -1355,8 +1355,8 @@ function api_users_show($type)
 
 	$user_info = api_get_user($a);
 
-	$condition = ["`owner-id` = ? AND `uid` = ? AND `verb` = ? AND `type` != 'activity' AND NOT `private`",
-		$user_info['pid'], api_user(), ACTIVITY_POST];
+	$condition = ['owner-id' => $user_info['pid'], 'uid' => api_user(),
+		'gravity' => [GRAVITY_PARENT, GRAVITY_COMMENT], 'private' => false];
 	$lastwall = dba::selectFirst('item', [], $condition, ['order' => ['id' => true]]);
 
 	if (DBM::is_result($lastwall)) {
@@ -1534,10 +1534,10 @@ function api_search($type)
 
 	$start = $page * $count;
 
-	$condition = ["`verb` = ? AND `item`.`id` > ?
+	$condition = ["`gravity` IN (?, ?) AND `item`.`id` > ?
 		AND (`item`.`uid` = 0 OR (`item`.`uid` = ? AND NOT `item`.`global`))
 		AND `item`.`body` LIKE CONCAT('%',?,'%')",
-		ACTIVITY_POST, $since_id, api_user(), $_REQUEST['q']];
+		GRAVITY_PARENT, GRAVITY_COMMENT, $since_id, api_user(), $_REQUEST['q']];
 
 	if ($max_id > 0) {
 		$condition[0] .= " AND `item`.`id` <= ?";
@@ -1597,7 +1597,8 @@ function api_statuses_home_timeline($type)
 
 	$start = $page * $count;
 
-	$condition = ["`uid` = ? AND `verb` = ? AND `item`.`id` > ?", api_user(), ACTIVITY_POST, $since_id];
+	$condition = ["`uid` = ? AND `gravity` IN (?, ?) AND `item`.`id` > ?",
+		api_user(), GRAVITY_PARENT, GRAVITY_COMMENT, $since_id];
 
 	if ($max_id > 0) {
 		$condition[0] .= " AND `item`.`id` <= ?";
@@ -1625,7 +1626,7 @@ function api_statuses_home_timeline($type)
 	}
 
 	if (!empty($idarray)) {
-		$unseen = dba::exists('item', ['unseen' => true, 'id' => $idarray]);
+		$unseen = Item::exists(['unseen' => true, 'id' => $idarray]);
 		if ($unseen) {
 			Item::update(['unseen' => false], ['unseen' => true, 'id' => $idarray]);
 		}
@@ -1680,8 +1681,8 @@ function api_statuses_public_timeline($type)
 	$sql_extra = '';
 
 	if ($exclude_replies && !$conversation_id) {
-		$condition = ["`verb` = ? AND `iid` > ? AND NOT `private` AND `wall` AND NOT `user`.`hidewall`",
-			ACTIVITY_POST, $since_id];
+		$condition = ["`gravity` IN (?, ?) AND `iid` > ? AND NOT `private` AND `wall` AND NOT `user`.`hidewall`",
+			GRAVITY_PARENT, GRAVITY_COMMENT, $since_id];
 
 		if ($max_id > 0) {
 			$condition[0] .= " AND `thread`.`iid` <= ?";
@@ -1693,8 +1694,8 @@ function api_statuses_public_timeline($type)
 
 		$r = Item::inArray($statuses);
 	} else {
-		$condition = ["`verb` = ? AND `id` > ? AND NOT `private` AND `wall` AND NOT `user`.`hidewall` AND `item`.`origin`",
-			ACTIVITY_POST, $since_id];
+		$condition = ["`gravity` IN (?, ?) AND `id` > ? AND NOT `private` AND `wall` AND NOT `user`.`hidewall` AND `item`.`origin`",
+			GRAVITY_PARENT, GRAVITY_COMMENT, $since_id];
 
 		if ($max_id > 0) {
 			$condition[0] .= " AND `item`.`id` <= ?";
@@ -1756,8 +1757,8 @@ function api_statuses_networkpublic_timeline($type)
 	}
 	$start = ($page - 1) * $count;
 
-	$condition = ["`uid` = 0 AND `verb` = ? AND `thread`.`iid` > ? AND NOT `private`",
-		ACTIVITY_POST, $since_id];
+	$condition = ["`uid` = 0 AND `gravity` IN (?, ?) AND `thread`.`iid` > ? AND NOT `private`",
+		GRAVITY_PARENT, GRAVITY_COMMENT, $since_id];
 
 	if ($max_id > 0) {
 		$condition[0] .= " AND `thread`.`iid` <= ?";
@@ -1829,10 +1830,10 @@ function api_statuses_show($type)
 	$id = $item['id'];
 
 	if ($conversation) {
-		$condition = ['parent' => $id, 'verb' => ACTIVITY_POST];
+		$condition = ['parent' => $id, 'gravity' => [GRAVITY_PARENT, GRAVITY_COMMENT]];
 		$params = ['order' => ['id' => true]];
 	} else {
-		$condition = ['id' => $id, 'verb' => ACTIVITY_POST];
+		$condition = ['id' => $id, 'gravity' => [GRAVITY_PARENT, GRAVITY_COMMENT]];
 		$params = [];
 	}
 
@@ -1908,8 +1909,8 @@ function api_conversation_show($type)
 
 	$id = $parent['id'];
 
-	$condition = ["`parent` = ? AND `uid` IN (0, ?) AND `verb` = ? AND `item`.`id` > ?",
-		$id, api_user(), ACTIVITY_POST, $since_id];
+	$condition = ["`parent` = ? AND `uid` IN (0, ?) AND `gravity` IN (?, ?) AND `item`.`id` > ?",
+		$id, api_user(), GRAVITY_PARENT, GRAVITY_COMMENT, $since_id];
 
 	if ($max_id > 0) {
 		$condition[0] .= " AND `item`.`id` <= ?";
@@ -2077,9 +2078,9 @@ function api_statuses_mentions($type)
 
 	$start = ($page - 1) * $count;
 
-	$condition = ["`uid` = ? AND `verb` = ? AND `item`.`id` > ? AND `author-id` != ?
+	$condition = ["`uid` = ? AND `gravity` IN (?, ?) AND `item`.`id` > ? AND `author-id` != ?
 		AND `item`.`parent` IN (SELECT `iid` FROM `thread` WHERE `thread`.`uid` = ? AND `thread`.`mention` AND NOT `thread`.`ignored`)",
-		api_user(), ACTIVITY_POST, $since_id, $user_info['pid'], api_user()];
+		api_user(), GRAVITY_PARENT, GRAVITY_COMMENT, $since_id, $user_info['pid'], api_user()];
 
 	if ($max_id > 0) {
 		$condition[0] .= " AND `item`.`id` <= ?";
@@ -2145,8 +2146,8 @@ function api_statuses_user_timeline($type)
 	}
 	$start = ($page - 1) * $count;
 
-	$condition = ["`uid` = ? AND `verb` = ? AND `item`.`id` > ? AND `item`.`contact-id` = ?",
-		api_user(), ACTIVITY_POST, $since_id, $user_info['cid']];
+	$condition = ["`uid` = ? AND `gravity` IN (?, ?) AND `item`.`id` > ? AND `item`.`contact-id` = ?",
+		api_user(), GRAVITY_PARENT, GRAVITY_COMMENT, $since_id, $user_info['cid']];
 
 	if ($user_info['self'] == 1) {
 		$condition[0] .= ' AND `item`.`wall` ';
@@ -2299,8 +2300,8 @@ function api_favorites($type)
 
 		$start = $page*$count;
 
-		$condition = ["`uid` = ? AND `verb` = ? AND `id` > ? AND `starred`",
-			api_user(), ACTIVITY_POST, $since_id];
+		$condition = ["`uid` = ? AND `gravity` IN (?, ?) AND `id` > ? AND `starred`",
+			api_user(), GRAVITY_PARENT, GRAVITY_COMMENT, $since_id];
 
 		$params = ['order' => ['id' => true], 'limit' => [$start, $count]];
 
@@ -3099,8 +3100,8 @@ function api_lists_statuses($type)
 
 	$start = $page * $count;
 
-	$condition = ["`uid` = ? AND `verb` = ? AND `id` > ? AND `group_member`.`gid` = ?",
-		api_user(), ACTIVITY_POST, $since_id, $_REQUEST['list_id']];
+	$condition = ["`uid` = ? AND `gravity` IN (?, ?) AND `id` > ? AND `group_member`.`gid` = ?",
+		api_user(), GRAVITY_PARENT, GRAVITY_COMMENT, $since_id, $_REQUEST['list_id']];
 
 	if ($max_id > 0) {
 		$condition[0] .= " AND `item`.`id` <= ?";
@@ -4630,8 +4631,8 @@ function prepare_photo_data($type, $scale, $photo_id)
 	$data['photo']['friendica_activities'] = api_format_items_activities($item, $type);
 
 	// retrieve comments on photo
-	$condition = ["`parent` = ? AND `uid` = ? AND (`verb` = ? OR `type`='photo')",
-		$item[0]['parent'], api_user(), ACTIVITY_POST];
+	$condition = ["`parent` = ? AND `uid` = ? AND (`gravity` IN (?, ?) OR `type`='photo')",
+		$item[0]['parent'], api_user(), GRAVITY_PARENT, GRAVITY_COMMENT];
 
 	$statuses = Item::selectForUser(api_user(), [], $condition);
 
diff --git a/include/enotify.php b/include/enotify.php
index 00459ac5c..be9468dd8 100644
--- a/include/enotify.php
+++ b/include/enotify.php
@@ -740,9 +740,9 @@ function check_item_notification($itemid, $uid, $defaulttype = "") {
 	// We need the additional check for the "local_profile" because of mixed situations on connector networks
 	$item = q("SELECT `id`, `mention`, `tag`,`parent`, `title`, `body`, `author-id`, `guid`,
 			`parent-uri`, `uri`, `contact-id`, `network`
-			FROM `item` WHERE `id` = %d AND `verb` IN ('%s', '') AND `type` != 'activity' AND
+			FROM `item` WHERE `id` = %d AND `gravity` IN (%d, %d) AND
 				NOT (`author-id` IN ($contact_list)) LIMIT 1",
-		intval($itemid), dbesc(ACTIVITY_POST));
+		intval($itemid), intval(GRAVITY_PARENT), intval(GRAVITY_COMMENT));
 	if (!$item)
 		return false;
 
diff --git a/mod/item.php b/mod/item.php
index 2830cae2c..0a3c3e2fa 100644
--- a/mod/item.php
+++ b/mod/item.php
@@ -567,7 +567,7 @@ function item_post(App $a) {
 		$network = NETWORK_DFRN;
 	}
 
-	$gravity = ($parent ? 6 : 0);
+	$gravity = ($parent ? GRAVITY_COMMENT : GRAVITY_PARENT);
 
 	// even if the post arrived via API we are considering that it
 	// originated on this site by default for determining relayability.
diff --git a/mod/network.php b/mod/network.php
index 61e4e779e..442ae669b 100644
--- a/mod/network.php
+++ b/mod/network.php
@@ -756,7 +756,7 @@ function networkThreadedView(App $a, $update, $parent)
 			// Load all unseen items
 			$sql_extra4 = "`item`.`unseen`";
 			if (Config::get("system", "like_no_comment")) {
-				$sql_extra4 .= " AND `item`.`verb` = '".ACTIVITY_POST."'";
+				$sql_extra4 .= " AND `item`.`gravity` IN (" . GRAVITY_PARENT . "," . GRAVITY_COMMENT . ")";
 			}
 			if ($order === 'post') {
 				// Only show toplevel posts when updating posts in this order mode
diff --git a/mod/photos.php b/mod/photos.php
index f54bc6244..34eea0c64 100644
--- a/mod/photos.php
+++ b/mod/photos.php
@@ -640,6 +640,7 @@ function photos_post(App $a)
 					$arr['deny_gid']      = $p[0]['deny_gid'];
 					$arr['visible']       = 1;
 					$arr['verb']          = ACTIVITY_TAG;
+					$arr['gravity']       = GRAVITY_PARENT;
 					$arr['object-type']   = ACTIVITY_OBJ_PERSON;
 					$arr['target-type']   = ACTIVITY_OBJ_IMAGE;
 					$arr['tag']           = $tagged[4];
diff --git a/mod/profile.php b/mod/profile.php
index a6075b01c..8d156cbd6 100644
--- a/mod/profile.php
+++ b/mod/profile.php
@@ -243,17 +243,14 @@ function profile_content(App $a, $update = 0)
 
 		$r = q("SELECT distinct(parent) AS `item_id`, `item`.`network` AS `item_network`, `item`.`created`
 			FROM `item` INNER JOIN `contact` ON `contact`.`id` = `item`.`contact-id`
-			AND `contact`.`blocked` = 0 AND `contact`.`pending` = 0
-			WHERE `item`.`uid` = %d AND `item`.`visible` = 1 AND
-			(`item`.`deleted` = 0 OR item.verb = '" . ACTIVITY_LIKE . "'
-			OR item.verb = '" . ACTIVITY_DISLIKE . "' OR item.verb = '" . ACTIVITY_ATTEND . "'
-			OR item.verb = '" . ACTIVITY_ATTENDNO . "' OR item.verb = '" . ACTIVITY_ATTENDMAYBE . "')
-			AND `item`.`moderated` = 0
-			AND `item`.`wall` = 1
+			AND NOT `contact`.`blocked` AND NOT `contact`.`pending`
+			WHERE `item`.`uid` = %d AND `item`.`visible` AND
+			(NOT `item`.`deleted` OR `item`.`gravity` = %d)
+			AND NOT `item`.`moderated` AND `item`.`wall`
 			$sql_extra4
 			$sql_extra
 			ORDER BY `item`.`created` DESC",
-			intval($a->profile['profile_uid'])
+			intval($a->profile['profile_uid']), intval(GRAVITY_ACTIVITY)
 		);
 
 		if (!DBM::is_result($r)) {
diff --git a/mod/subthread.php b/mod/subthread.php
index 0b6f4ecaa..e05aa5fec 100644
--- a/mod/subthread.php
+++ b/mod/subthread.php
@@ -125,7 +125,7 @@ EOT;
 	$arr['type'] = 'activity';
 	$arr['wall'] = $item['wall'];
 	$arr['origin'] = 1;
-	$arr['gravity'] = GRAVITY_LIKE;
+	$arr['gravity'] = GRAVITY_ACTIVITY;
 	$arr['parent'] = $item['id'];
 	$arr['parent-uri'] = $item['uri'];
 	$arr['thr-parent'] = $item['uri'];
diff --git a/src/Database/DBStructure.php b/src/Database/DBStructure.php
index eaf54cee2..8fb2afddb 100644
--- a/src/Database/DBStructure.php
+++ b/src/Database/DBStructure.php
@@ -1270,6 +1270,7 @@ class DBStructure
 						"target-type" => ["type" => "varchar(100)", "not null" => "1", "default" => "", "comment" => "ActivityStreams target type if applicable (URI)"],
 						"target" => ["type" => "text", "comment" => "JSON encoded target structure if used"],
 						"plink" => ["type" => "varchar(255)", "not null" => "1", "default" => "", "comment" => "permalink or URL to a displayable copy of the message at its source"],
+						"verb" => ["type" => "varchar(100)", "not null" => "1", "default" => "", "comment" => "ActivityStreams verb"],
 						],
 				"indexes" => [
 						"PRIMARY" => ["id"],
diff --git a/src/Model/Contact.php b/src/Model/Contact.php
index 973e5b5a2..fe9869c6f 100644
--- a/src/Model/Contact.php
+++ b/src/Model/Contact.php
@@ -1064,8 +1064,8 @@ class Contact extends BaseObject
 
 		$contact = ($r[0]["contact-type"] == ACCOUNT_TYPE_COMMUNITY ? 'owner-id' : 'author-id');
 
-		$condition = ["`$contact` = ? AND `verb` = ? AND " . $sql,
-			$author_id, ACTIVITY_POST, local_user()];
+		$condition = ["`$contact` = ? AND `gravity` IN (?, ?) AND " . $sql,
+			$author_id, GRAVITY_PARENT, GRAVITY_COMMENT, local_user()];
 		$params = ['order' => ['created' => true],
 			'limit' => [$a->pager['start'], $a->pager['itemspage']]];
 		$r = Item::selectForUser(local_user(), [], $condition, $params);
diff --git a/src/Model/Item.php b/src/Model/Item.php
index 6fe4a575d..9fafe26aa 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -58,7 +58,7 @@ class Item extends BaseObject
 
 	// Field list for "item-content" table that is mixed with the item table
 	const CONTENT_FIELDLIST = ['title', 'content-warning', 'body', 'location',
-			'coord', 'app', 'rendered-hash', 'rendered-html',
+			'coord', 'app', 'rendered-hash', 'rendered-html', 'verb',
 			'object-type', 'object', 'target-type', 'target'];
 
 	// All fields in the item table
@@ -86,7 +86,7 @@ class Item extends BaseObject
 
 		// Fetch data from the item-content table whenever there is content there
 		foreach (self::CONTENT_FIELDLIST as $field) {
-			if (is_null($row[$field]) && !is_null($row['item-' . $field])) {
+			if (empty($row[$field]) && !empty($row['item-' . $field])) {
 				$row[$field] = $row['item-' . $field];
 			}
 			unset($row['item-' . $field]);
@@ -143,6 +143,27 @@ class Item extends BaseObject
 		return $data;
 	}
 
+	/**
+	 * @brief Check if item data exists
+	 *
+	 * @param array $condition array of fields for condition
+	 *
+	 * @return boolean Are there rows for that condition?
+	 */
+	public static function exists($condition) {
+		$stmt = self::select(['id'], $condition, ['limit' => 1]);
+
+		if (is_bool($stmt)) {
+			$retval = $stmt;
+		} else {
+			$retval = (dba::num_rows($stmt) > 0);
+		}
+
+		dba::close($stmt);
+
+		return $retval;
+	}
+
 	/**
 	 * Retrieve a single record from the item table for a given user and returns it in an associative array
 	 *
@@ -377,12 +398,12 @@ class Item extends BaseObject
 
 		$fields['item'] = ['id', 'uid', 'parent', 'uri', 'parent-uri', 'thr-parent', 'guid',
 			'contact-id', 'owner-id', 'author-id', 'type', 'wall', 'gravity', 'extid',
-			'created', 'edited', 'commented', 'received', 'changed', 'verb',
-			'postopts', 'plink', 'resource-id', 'event-id', 'tag', 'attach', 'inform',
+			'created', 'edited', 'commented', 'received', 'changed', 'postopts',
+			'plink', 'resource-id', 'event-id', 'tag', 'attach', 'inform',
 			'file', 'allow_cid', 'allow_gid', 'deny_cid', 'deny_gid',
 			'private', 'pubmail', 'moderated', 'visible', 'starred', 'bookmark',
 			'unseen', 'deleted', 'origin', 'forum_mode', 'mention', 'global',
-			'id' => 'item_id', 'network'];
+			'id' => 'item_id', 'network', 'icid'];
 
 		$fields['item-content'] = self::CONTENT_FIELDLIST;
 
@@ -728,15 +749,14 @@ class Item extends BaseObject
 		self::deleteTagsFromItem($item);
 
 		// Set the item to "deleted"
-		dba::update('item', ['deleted' => true, 'title' => '', 'body' => '',
-					'edited' => DateTimeFormat::utcNow(), 'changed' => DateTimeFormat::utcNow()],
+		dba::update('item', ['deleted' => true, 'edited' => DateTimeFormat::utcNow(), 'changed' => DateTimeFormat::utcNow()],
 				['id' => $item['id']]);
 
 		Term::insertFromTagFieldByItemId($item['id']);
 		Term::insertFromFileFieldByItemId($item['id']);
 		self::deleteThread($item['id'], $item['parent-uri']);
 
-		if (!dba::exists('item', ["`uri` = ? AND `uid` != 0 AND NOT `deleted`", $item['uri']])) {
+		if (!self::exists(["`uri` = ? AND `uid` != 0 AND NOT `deleted`", $item['uri']])) {
 			self::delete(['uri' => $item['uri'], 'uid' => 0, 'deleted' => false], $priority);
 		}
 
@@ -953,18 +973,21 @@ class Item extends BaseObject
 			$item['parent-uri'] = $item['thr-parent'];
 		}
 
-		if (x($item, 'gravity')) {
+		$item['type'] = defaults($item, 'type', 'remote');
+
+		if (isset($item['gravity'])) {
 			$item['gravity'] = intval($item['gravity']);
 		} elseif ($item['parent-uri'] === $item['uri']) {
-			$item['gravity'] = 0;
-		} elseif (activity_match($item['verb'],ACTIVITY_POST)) {
-			$item['gravity'] = 6;
+			$item['gravity'] = GRAVITY_PARENT;
+		} elseif (activity_match($item['verb'], ACTIVITY_POST)) {
+			$item['gravity'] = GRAVITY_COMMENT;
+		} elseif ($item['type'] == 'activity') {
+			$item['gravity'] = GRAVITY_ACTIVITY;
 		} else {
-			$item['gravity'] = 6;   // extensible catchall
+			$item['gravity'] = GRAVITY_UNKNOWN;   // Should not happen
+			logger('Unknown gravity for verb: ' . $item['verb'] . ' - type: ' . $item['type'], LOGGER_DEBUG);
 		}
 
-		$item['type'] = defaults($item, 'type', 'remote');
-
 		$uid = intval($item['uid']);
 
 		// check for create date and expire time
@@ -1117,7 +1140,7 @@ class Item extends BaseObject
 		// Checking if there is already an item with the same guid
 		logger('Checking for an item for user '.$item['uid'].' on network '.$item['network'].' with the guid '.$item['guid'], LOGGER_DEBUG);
 		$condition = ['guid' => $item['guid'], 'network' => $item['network'], 'uid' => $item['uid']];
-		if (dba::exists('item', $condition)) {
+		if (self::exists($condition)) {
 			logger('found item with guid '.$item['guid'].' for user '.$item['uid'].' on network '.$item['network'], LOGGER_DEBUG);
 			return 0;
 		}
@@ -1219,7 +1242,7 @@ class Item extends BaseObject
 					logger('$force_parent=true, reply converted to top-level post.');
 					$parent_id = 0;
 					$item['parent-uri'] = $item['uri'];
-					$item['gravity'] = 0;
+					$item['gravity'] = GRAVITY_PARENT;
 				} else {
 					logger('item parent '.$item['parent-uri'].' for '.$item['uid'].' was not found - ignoring item');
 					return 0;
@@ -1231,7 +1254,7 @@ class Item extends BaseObject
 
 		$condition = ["`uri` = ? AND `network` IN (?, ?) AND `uid` = ?",
 			$item['uri'], $item['network'], NETWORK_DFRN, $item['uid']];
-		if (dba::exists('item', $condition)) {
+		if (self::exists($condition)) {
 			logger('duplicated item with the same uri found. '.print_r($item,true));
 			return 0;
 		}
@@ -1239,7 +1262,7 @@ class Item extends BaseObject
 		// On Friendica and Diaspora the GUID is unique
 		if (in_array($item['network'], [NETWORK_DFRN, NETWORK_DIASPORA])) {
 			$condition = ['guid' => $item['guid'], 'uid' => $item['uid']];
-			if (dba::exists('item', $condition)) {
+			if (self::exists($condition)) {
 				logger('duplicated item with the same guid found. '.print_r($item,true));
 				return 0;
 			}
@@ -1247,7 +1270,7 @@ class Item extends BaseObject
 			// Check for an existing post with the same content. There seems to be a problem with OStatus.
 			$condition = ["`body` = ? AND `network` = ? AND `created` = ? AND `contact-id` = ? AND `uid` = ?",
 					$item['body'], $item['network'], $item['created'], $item['contact-id'], $item['uid']];
-			if (dba::exists('item', $condition)) {
+			if (self::exists($condition)) {
 				logger('duplicated item with the same body found. '.print_r($item,true));
 				return 0;
 			}
@@ -1260,7 +1283,7 @@ class Item extends BaseObject
 			// Set the global flag on all items if this was a global item entry
 			dba::update('item', ['global' => true], ['uri' => $item["uri"]]);
 		} else {
-			$item["global"] = dba::exists('item', ['uid' => 0, 'uri' => $item["uri"]]);
+			$item["global"] = self::exists(['uid' => 0, 'uri' => $item["uri"]]);
 		}
 
 		// ACL settings
@@ -1301,7 +1324,7 @@ class Item extends BaseObject
 		 * An unique index would help - but the limitations of MySQL (maximum size of index values) prevent this.
 		 */
 		if ($item["uid"] == 0) {
-			if (dba::exists('item', ['uri' => trim($item['uri']), 'uid' => 0])) {
+			if (self::exists(['uri' => trim($item['uri']), 'uid' => 0])) {
 				logger('Global item already stored. URI: '.$item['uri'].' on network '.$item['network'], LOGGER_DEBUG);
 				return 0;
 			}
@@ -1668,7 +1691,7 @@ class Item extends BaseObject
 		if (DBM::is_result($item) && ($item["allow_cid"] == '') && ($item["allow_gid"] == '') &&
 			($item["deny_cid"] == '') && ($item["deny_gid"] == '')) {
 
-			if (!dba::exists('item', ['uri' => $item['uri'], 'uid' => 0])) {
+			if (!self::exists(['uri' => $item['uri'], 'uid' => 0])) {
 				// Preparing public shadow (removing user specific data)
 				$item['uid'] = 0;
 				unset($item['id']);
@@ -1722,12 +1745,12 @@ class Item extends BaseObject
 		}
 
 		// Is there a shadow parent?
-		if (!dba::exists('item', ['uri' => $item['parent-uri'], 'uid' => 0])) {
+		if (!self::exists(['uri' => $item['parent-uri'], 'uid' => 0])) {
 			return;
 		}
 
 		// Is there already a shadow entry?
-		if (dba::exists('item', ['uri' => $item['uri'], 'uid' => 0])) {
+		if (self::exists(['uri' => $item['uri'], 'uid' => 0])) {
 			return;
 		}
 
@@ -1757,7 +1780,7 @@ class Item extends BaseObject
 
 		// If this was a comment to a Diaspora post we don't get our comment back.
 		// This means that we have to distribute the comment by ourselves.
-		if ($origin && dba::exists('item', ['id' => $parent, 'network' => NETWORK_DIASPORA])) {
+		if ($origin && self::exists(['id' => $parent, 'network' => NETWORK_DIASPORA])) {
 			self::distribute($public_shadow);
 		}
 	}
@@ -2567,30 +2590,32 @@ class Item extends BaseObject
 		// event participation are essentially radio toggles. If you make a subsequent choice,
 		// we need to eradicate your first choice.
 		if ($event_verb_flag) {
-			$verbs = "'" . dbesc(ACTIVITY_ATTEND) . "', '" . dbesc(ACTIVITY_ATTENDNO) . "', '" . dbesc(ACTIVITY_ATTENDMAYBE) . "'";
+			$verbs = [ACTIVITY_ATTEND, ACTIVITY_ATTENDNO, ACTIVITY_ATTENDMAYBE];
 		} else {
-			$verbs = "'".dbesc($activity)."'";
+			$verbs = $activity;
 		}
 
-		/// @todo This query is expected to be a performance eater due to the "OR" - it has to be changed totally
-		$existing_like = q("SELECT `id`, `guid`, `verb` FROM `item`
-			WHERE `verb` IN ($verbs)
-			AND `deleted` = 0
-			AND `author-id` = %d
-			AND `uid` = %d
-			AND (`parent` = '%s' OR `parent-uri` = '%s' OR `thr-parent` = '%s')
-			LIMIT 1",
-			intval($author_contact['id']),
-			intval($item['uid']),
-			dbesc($item_id), dbesc($item_id), dbesc($item['uri'])
-		);
+		$base_condition = ['verb' => $verbs, 'deleted' => false, 'gravity' => GRAVITY_ACTIVITY,
+			'author-id' => $author_contact['id'], 'uid' => item['uid']];
+
+		$condition = array_merge($base_condition, ['parent' => $item_id]);
+		$like_item = self::selectFirst(['id', 'guid', 'verb'], $condition);
+
+		if (!DBM::is_result($like_item)) {
+			$condition = array_merge($base_condition, ['parent-uri' => $item_id]);
+			$like_item = self::selectFirst(['id', 'guid', 'verb'], $condition);
+		}
+
+		if (!DBM::is_result($like_item)) {
+			$condition = array_merge($base_condition, ['thr-parent' => $item_id]);
+			$like_item = self::selectFirst(['id', 'guid', 'verb'], $condition);
+		}
 
 		// If it exists, mark it as deleted
-		if (DBM::is_result($existing_like)) {
-			$like_item = $existing_like[0];
-
+		if (DBM::is_result($like_item)) {
 			// Already voted, undo it
 			$fields = ['deleted' => true, 'unseen' => true, 'changed' => DateTimeFormat::utcNow()];
+			/// @todo Consider using self::update - but before doing so, check the side effects
 			dba::update('item', $fields, ['id' => $like_item['id']]);
 
 			// Clean up the Diaspora signatures for this like
@@ -2644,7 +2669,7 @@ EOT;
 			'type'          => 'activity',
 			'wall'          => $item['wall'],
 			'origin'        => 1,
-			'gravity'       => GRAVITY_LIKE,
+			'gravity'       => GRAVITY_ACTIVITY,
 			'parent'        => $item['id'],
 			'parent-uri'    => $item['uri'],
 			'thr-parent'    => $item['uri'],
@@ -2754,7 +2779,7 @@ EOT;
 
 		if ($itemuri != "") {
 			$condition = ["`uri` = ? AND NOT `deleted` AND NOT (`uid` IN (?, 0))", $itemuri, $item["uid"]];
-			if (!dba::exists('item', $condition)) {
+			if (!self::exists($condition)) {
 				dba::delete('item', ['uri' => $itemuri, 'uid' => 0]);
 				logger("deleteThread: Deleted shadow for item ".$itemuri, LOGGER_DEBUG);
 			}
diff --git a/src/Model/Term.php b/src/Model/Term.php
index b211e7d2e..858714209 100644
--- a/src/Model/Term.php
+++ b/src/Model/Term.php
@@ -24,7 +24,7 @@ class Term
 		$profile_base_diaspora = $profile_data['host'] . $profile_path . '/u/';
 
 		$fields = ['guid', 'uid', 'id', 'edited', 'deleted', 'created', 'received', 'title', 'body', 'tag', 'parent'];
-		$message = dba::selectFirst('item', $fields, ['id' => $itemid]);
+		$message = Item::selectFirst($fields, ['id' => $itemid]);
 		if (!DBM::is_result($message)) {
 			return;
 		}
@@ -130,7 +130,7 @@ class Term
 	 */
 	public static function insertFromFileFieldByItemId($itemid)
 	{
-		$message = dba::selectFirst('item', ['uid', 'deleted', 'file'], ['id' => $itemid]);
+		$message = Item::selectFirst(['uid', 'deleted', 'file'], ['id' => $itemid]);
 		if (!DBM::is_result($message)) {
 			return;
 		}
diff --git a/src/Protocol/DFRN.php b/src/Protocol/DFRN.php
index 1047ffdfe..c1e116f2f 100644
--- a/src/Protocol/DFRN.php
+++ b/src/Protocol/DFRN.php
@@ -2310,18 +2310,18 @@ class DFRN
 			) {
 				$is_like = true;
 				$item["type"] = "activity";
-				$item["gravity"] = GRAVITY_LIKE;
+				$item["gravity"] = GRAVITY_ACTIVITY;
 				// only one like or dislike per person
 				// splitted into two queries for performance issues
-				$condition = ['uid' => $item["uid"], 'author-id' => $item["author-id"],
+				$condition = ['uid' => $item["uid"], 'author-id' => $item["author-id"], 'gravity' => GRAVITY_ACTIVITY,
 					'verb' => $item["verb"], 'parent-uri' => $item["parent-uri"]];
-				if (dba::exists('item', $condition)) {
+				if (Item::exists($condition)) {
 					return false;
 				}
 
-				$condition = ['uid' => $item["uid"], 'author-id' => $item["author-id"],
+				$condition = ['uid' => $item["uid"], 'author-id' => $item["author-id"], 'gravity' => GRAVITY_ACTIVITY,
 					'verb' => $item["verb"], 'thr-parent' => $item["parent-uri"]];
-				if (dba::exists('item', $condition)) {
+				if (Item::exists($condition)) {
 					return false;
 				}
 			} else {
@@ -2770,7 +2770,7 @@ class DFRN
 		// Comments can be deleted by the thread owner or comment owner
 		if (($item['id'] != $item['parent']) && ($item['contact-id'] != $importer["id"])) {
 			$condition = ['id' => $item['parent'], 'contact-id' => $importer["id"]];
-			if (!dba::exists('item', $condition)) {
+			if (!Item::exists($condition)) {
 				logger("Item with uri " . $uri . " wasn't found or mustn't be deleted by contact " . $importer["id"] . " - ignoring deletion.", LOGGER_DEBUG);
 				return;
 			}
diff --git a/src/Protocol/Diaspora.php b/src/Protocol/Diaspora.php
index 29fb42a80..6ef529b7f 100644
--- a/src/Protocol/Diaspora.php
+++ b/src/Protocol/Diaspora.php
@@ -2049,7 +2049,7 @@ class Diaspora
 
 		$datarray["type"] = "activity";
 		$datarray["verb"] = $verb;
-		$datarray["gravity"] = GRAVITY_LIKE;
+		$datarray["gravity"] = GRAVITY_ACTIVITY;
 		$datarray["parent-uri"] = $parent_item["uri"];
 
 		$datarray["object-type"] = ACTIVITY_OBJ_NOTE;
diff --git a/src/Protocol/OStatus.php b/src/Protocol/OStatus.php
index 288cbfed1..ffa698ee8 100644
--- a/src/Protocol/OStatus.php
+++ b/src/Protocol/OStatus.php
@@ -416,7 +416,7 @@ class OStatus
 			}
 
 			// Deletions come with the same uri, so we check for duplicates after processing deletions
-			if (dba::exists('item', ['uid' => $importer["uid"], 'uri' => $item["uri"]])) {
+			if (Item::exists(['uid' => $importer["uid"], 'uri' => $item["uri"]])) {
 				logger('Post with URI '.$item["uri"].' already existed for user '.$importer["uid"].'.', LOGGER_DEBUG);
 				continue;
 			} else {
@@ -451,7 +451,7 @@ class OStatus
 
 				$item["verb"] = ACTIVITY_LIKE;
 				$item["parent-uri"] = $orig_uri;
-				$item["gravity"] = GRAVITY_LIKE;
+				$item["gravity"] = GRAVITY_ACTIVITY;
 			}
 
 			// http://activitystrea.ms/schema/1.0/rsvp-yes
@@ -489,7 +489,7 @@ class OStatus
 					}
 				} else {
 					// But we will only import complete threads
-					$valid = dba::exists('item', ['uid' => $importer["uid"], 'uri' => self::$itemlist[0]['parent-uri']]);
+					$valid = Item::exists(['uid' => $importer["uid"], 'uri' => self::$itemlist[0]['parent-uri']]);
 					if ($valid) {
 						logger("Item with uri ".self::$itemlist[0]["uri"]." belongs to parent ".self::$itemlist[0]['parent-uri']." of user ".$importer["uid"].". It will be imported.", LOGGER_DEBUG);
 					}
@@ -506,7 +506,7 @@ class OStatus
 						}
 					}
 					foreach (self::$itemlist as $item) {
-						$found = dba::exists('item', ['uid' => $importer["uid"], 'uri' => $item["uri"]]);
+						$found = Item::exists(['uid' => $importer["uid"], 'uri' => $item["uri"]]);
 						if ($found) {
 							logger("Item with uri ".$item["uri"]." for user ".$importer["uid"]." already exists.", LOGGER_DEBUG);
 						} elseif ($item['contact-id'] < 0) {
@@ -537,8 +537,8 @@ class OStatus
 	 */
 	private static function deleteNotice($item)
 	{
-		$condition = ['uid' => $item['uid'], 'author-link' => $item['author-link'], 'uri' => $item['uri']];
-		if (!dba::exists('item', $condition)) {
+		$condition = ['uid' => $item['uid'], 'author-id' => $item['author-id'], 'uri' => $item['uri']];
+		if (!Item::exists($condition)) {
 			logger('Item from '.$item['author-link'].' with uri '.$item['uri'].' for user '.$item['uid']." wasn't found. We don't delete it.");
 			return;
 		}
@@ -674,7 +674,7 @@ class OStatus
 		}
 
 		if (isset($item["parent-uri"])) {
-			if (!dba::exists('item', ['uid' => $importer["uid"], 'uri' => $item['parent-uri']])) {
+			if (!Item::exists(['uid' => $importer["uid"], 'uri' => $item['parent-uri']])) {
 				if ($related != '') {
 					self::fetchRelated($related, $item["parent-uri"], $importer);
 				}
diff --git a/src/Worker/OnePoll.php b/src/Worker/OnePoll.php
index 43526a372..eaef5f252 100644
--- a/src/Worker/OnePoll.php
+++ b/src/Worker/OnePoll.php
@@ -389,7 +389,7 @@ class OnePoll
 							// Have we seen it before?
 							$fields = ['deleted', 'id'];
 							$condition = ['uid' => $importer_uid, 'uri' => $datarray['uri']];
-							$item = dba::selectFirst('item', $fields, $condition);
+							$item = Item::selectFirst($fields, $condition);
 							if (DBM::is_result($item)) {
 								logger("Mail: Seen before ".$msg_uid." for ".$mailconf['user']." UID: ".$importer_uid." URI: ".$datarray['uri'],LOGGER_DEBUG);
 
@@ -435,7 +435,7 @@ class OnePoll
 								$refs_arr = explode(' ', $raw_refs);
 								if (count($refs_arr)) {
 									for ($x = 0; $x < count($refs_arr); $x ++) {
-										$refs_arr[$x] = "'" . Email::msgid2iri(str_replace(['<', '>', ' '],['', '', ''],dbesc($refs_arr[$x]))) . "'";
+										$refs_arr[$x] = Email::msgid2iri(str_replace(['<', '>', ' '],['', '', ''], $refs_arr[$x]));
 									}
 								}
 								$condition = ['uri' => $refs_arr, 'uid' => $importer_uid];