diff --git a/database.sql b/database.sql
index 1ca1f962b..8c4ab5bae 100644
--- a/database.sql
+++ b/database.sql
@@ -1,6 +1,6 @@
 -- ------------------------------------------
 -- Friendica 2021.03-dev (Red Hot Poker)
--- DB_UPDATE_VERSION 1387
+-- DB_UPDATE_VERSION 1388
 -- ------------------------------------------
 
 
@@ -1643,7 +1643,7 @@ CREATE VIEW `post-view` AS SELECT
 			LEFT JOIN `item-content` ON `item-content`.`uri-id` = `item`.`uri-id`
 			LEFT JOIN `post-delivery-data` ON `post-delivery-data`.`uri-id` = `item`.`uri-id` AND `item`.`origin`
 			LEFT JOIN `permissionset` ON `permissionset`.`id` = `item`.`psid`
-			STRAIGHT_JOIN `item` AS `parent-item` ON `parent-item`.`id` = `item`.`parent`
+			STRAIGHT_JOIN `item` AS `parent-item` ON `parent-item`.`uri-id` = `item`.`parent-uri-id`
 			STRAIGHT_JOIN `contact` AS `parent-item-author` ON `parent-item-author`.`id` = `parent-item`.`author-id`;
 
 --
diff --git a/include/api.php b/include/api.php
index 5aba98918..ccb6f718e 100644
--- a/include/api.php
+++ b/include/api.php
@@ -1881,14 +1881,14 @@ function api_statuses_show($type)
 	$conversation = !empty($_REQUEST['conversation']);
 
 	// try to fetch the item for the local user - or the public item, if there is no local one
-	$uri_item = Post::selectFirst(['uri'], ['id' => $id]);
+	$uri_item = Post::selectFirst(['uri-id'], ['id' => $id]);
 	if (!DBA::isResult($uri_item)) {
-		throw new BadRequestException("There is no status with this id.");
+		throw new BadRequestException(sprintf("There is no status with the id %d", $id));
 	}
 
-	$item = Post::selectFirst(['id'], ['uri' => $uri_item['uri'], 'uid' => [0, api_user()]], ['order' => ['uid' => true]]);
+	$item = Post::selectFirst(['id'], ['uri-id' => $uri_item['uri-id'], 'uid' => [0, api_user()]], ['order' => ['uid' => true]]);
 	if (!DBA::isResult($item)) {
-		throw new BadRequestException("There is no status with this id.");
+		throw new BadRequestException(sprintf("There is no status with the uri-id %d for the given user.", $uri_item['uri-id']));
 	}
 
 	$id = $item['id'];
@@ -1905,7 +1905,7 @@ function api_statuses_show($type)
 
 	/// @TODO How about copying this to above methods which don't check $r ?
 	if (!DBA::isResult($statuses)) {
-		throw new BadRequestException("There is no status with this id.");
+		throw new BadRequestException(sprintf("There is no status or conversation with the id %d.", $id));
 	}
 
 	$ret = api_format_items(Post::toArray($statuses), $user_info, false, $type);
@@ -1964,12 +1964,12 @@ function api_conversation_show($type)
 	Logger::info(API_LOG_PREFIX . '{subaction}', ['module' => 'api', 'action' => 'conversation', 'subaction' => 'show', 'id' => $id]);
 
 	// try to fetch the item for the local user - or the public item, if there is no local one
-	$item = Post::selectFirst(['parent-uri'], ['id' => $id]);
+	$item = Post::selectFirst(['parent-uri-id'], ['id' => $id]);
 	if (!DBA::isResult($item)) {
 		throw new BadRequestException("There is no status with this id.");
 	}
 
-	$parent = Post::selectFirst(['id'], ['uri' => $item['parent-uri'], 'uid' => [0, api_user()]], ['order' => ['uid' => true]]);
+	$parent = Post::selectFirst(['id'], ['uri-id' => $item['parent-uri-id'], 'uid' => [0, api_user()]], ['order' => ['uid' => true]]);
 	if (!DBA::isResult($parent)) {
 		throw new BadRequestException("There is no status with this id.");
 	}
@@ -2171,11 +2171,11 @@ function api_statuses_mentions($type)
 
 	$start = max(0, ($page - 1) * $count);
 
-	$query = "SELECT `item`.`id` FROM `user-item`
-		INNER JOIN `item` ON `item`.`id` = `user-item`.`iid` AND `item`.`gravity` IN (?, ?)
-		WHERE (`user-item`.`hidden` IS NULL OR NOT `user-item`.`hidden`) AND
-			`user-item`.`uid` = ? AND `user-item`.`notification-type` & ? != 0
-			AND `user-item`.`iid` > ?";
+	$query = "`gravity` IN (?, ?) AND `id` IN (SELECT `iid` FROM `user-item`		
+		WHERE (`hidden` IS NULL OR NOT `hidden`) AND
+			`uid` = ? AND `notification-type` & ? != 0
+			AND `iid` > ?";
+
 	$condition = [GRAVITY_PARENT, GRAVITY_COMMENT, api_user(),
 		UserItem::NOTIF_EXPLICIT_TAGGED | UserItem::NOTIF_IMPLICIT_TAGGED |
 		UserItem::NOTIF_THREAD_COMMENT | UserItem::NOTIF_DIRECT_COMMENT |
@@ -2183,23 +2183,16 @@ function api_statuses_mentions($type)
 		$since_id];
 
 	if ($max_id > 0) {
-		$query .= " AND `item`.`id` <= ?";
+		$query .= " AND `iid` <= ?";
 		$condition[] = $max_id;
 	}
 
-	$query .= " ORDER BY `user-item`.`iid` DESC LIMIT ?, ?";
-	$condition[] = $start;
-	$condition[] = $count;
+	$query .= ")";
 
-	$useritems = DBA::p($query, $condition);
-	$itemids = [];
-	while ($useritem = DBA::fetch($useritems)) {
-		$itemids[] = $useritem['id'];
-	}
-	DBA::close($useritems);
+	array_unshift($condition, $query);
 
 	$params = ['order' => ['id' => true], 'limit' => [$start, $count]];
-	$statuses = Post::selectForUser(api_user(), [], ['id' => $itemids], $params);
+	$statuses = Post::selectForUser(api_user(), [], $condition, $params);
 
 	$ret = api_format_items(Post::toArray($statuses), $user_info, false, $type);
 
diff --git a/static/dbstructure.config.php b/static/dbstructure.config.php
index 18a0d5981..5199dae33 100644
--- a/static/dbstructure.config.php
+++ b/static/dbstructure.config.php
@@ -55,7 +55,7 @@
 use Friendica\Database\DBA;
 
 if (!defined('DB_UPDATE_VERSION')) {
-	define('DB_UPDATE_VERSION', 1387);
+	define('DB_UPDATE_VERSION', 1388);
 }
 
 return [
diff --git a/static/dbview.config.php b/static/dbview.config.php
index b987eab42..1a9f194b8 100644
--- a/static/dbview.config.php
+++ b/static/dbview.config.php
@@ -190,7 +190,7 @@
 			LEFT JOIN `item-content` ON `item-content`.`uri-id` = `item`.`uri-id`
 			LEFT JOIN `post-delivery-data` ON `post-delivery-data`.`uri-id` = `item`.`uri-id` AND `item`.`origin`
 			LEFT JOIN `permissionset` ON `permissionset`.`id` = `item`.`psid`
-			STRAIGHT_JOIN `item` AS `parent-item` ON `parent-item`.`id` = `item`.`parent`
+			STRAIGHT_JOIN `item` AS `parent-item` ON `parent-item`.`uri-id` = `item`.`parent-uri-id`
 			STRAIGHT_JOIN `contact` AS `parent-item-author` ON `parent-item-author`.`id` = `parent-item`.`author-id`"
 	],
 	"category-view" => [
diff --git a/tests/datasets/api.fixture.php b/tests/datasets/api.fixture.php
index 93b896ebf..f8c696c87 100644
--- a/tests/datasets/api.fixture.php
+++ b/tests/datasets/api.fixture.php
@@ -193,6 +193,9 @@ return [
 			'unseen'      => 1,
 			'body'        => 'Parent status',
 			'parent'      => 1,
+			'parent-uri-id' => 1,
+			'thr-parent-id' => 1,
+			'gravity'     => GRAVITY_PARENT,
 			'author-link' => 'http://localhost/profile/selfcontact',
 			'wall'        => 1,
 			'starred'     => 1,
@@ -217,6 +220,9 @@ return [
 			'unseen'      => 0,
 			'body'        => 'Reply',
 			'parent'      => 1,
+			'parent-uri-id' => 1,
+			'thr-parent-id' => 1,
+			'gravity'     => GRAVITY_COMMENT,
 			'author-link' => 'http://localhost/profile/selfcontact',
 			'wall'        => 1,
 			'starred'     => 0,
@@ -238,6 +244,9 @@ return [
 			'unseen'      => 0,
 			'body'        => 'Other user status',
 			'parent'      => 3,
+			'parent-uri-id' => 3,
+			'thr-parent-id' => 3,
+			'gravity'     => GRAVITY_PARENT,
 			'author-link' => 'http://localhost/profile/othercontact',
 			'wall'        => 1,
 			'starred'     => 0,
@@ -258,6 +267,9 @@ return [
 			'unseen'      => 0,
 			'body'        => 'Friend user reply',
 			'parent'      => 1,
+			'parent-uri-id' => 1,
+			'thr-parent-id' => 1,
+			'gravity'     => GRAVITY_COMMENT,
 			'author-link' => 'http://localhost/profile/othercontact',
 			'wall'        => 1,
 			'starred'     => 0,
@@ -279,6 +291,9 @@ return [
 			'unseen'      => 0,
 			'body'        => '[share]Shared status[/share]',
 			'parent'      => 1,
+			'parent-uri-id' => 1,
+			'thr-parent-id' => 1,
+			'gravity'     => GRAVITY_COMMENT,
 			'author-link' => 'http://localhost/profile/othercontact',
 			'wall'        => 1,
 			'starred'     => 0,
@@ -303,6 +318,9 @@ return [
 			'unseen'      => 0,
 			'body'        => 'Friend user status',
 			'parent'      => 6,
+			'parent-uri-id' => 6,
+			'thr-parent-id' => 6,
+			'gravity'     => GRAVITY_PARENT,
 			'author-link' => 'http://localhost/profile/othercontact',
 			'wall'        => 1,
 			'starred'     => 0,