3 files changed, 5 insertions, 5 deletions

diff --git a/classes/ccache.php b/classes/ccache.php
index 9c5547e7d..2f19140e0 100644
--- a/classes/ccache.php
+++ b/classes/ccache.php
@@ -141,7 +141,7 @@ class CCache {
 
 			$sth = $pdo->prepare("SELECT SUM(value) AS sv
 				FROM ttrss_counters_cache, ttrss_feeds
-				WHERE id = feed_id AND
+				WHERE ttrss_feeds.id = feed_id AND
 				(cat_id = :cat OR (:cat = 0 AND cat_id IS NULL)) AND
 				ttrss_counters_cache.owner_uid = :uid AND
 				ttrss_feeds.owner_uid = :uid");
diff --git a/classes/counters.php b/classes/counters.php
index 2de7d5a3a..cee901304 100644
--- a/classes/counters.php
+++ b/classes/counters.php
@@ -24,11 +24,11 @@ class Counters {
 
 		$pdo = DB::pdo();
 
-		$sth = $pdo->prepare("SELECT id AS cat_id, value AS unread,
+		$sth = $pdo->prepare("SELECT ttrss_feed_categories.id AS cat_id, value AS unread,
 			(SELECT COUNT(id) FROM ttrss_feed_categories AS c2
 				WHERE c2.parent_cat = ttrss_feed_categories.id) AS num_children
 			FROM ttrss_feed_categories, ttrss_cat_counters_cache
-			WHERE ttrss_cat_counters_cache.feed_id = id AND
+			WHERE ttrss_cat_counters_cache.feed_id = ttrss_feed_categories.id AND
 			ttrss_cat_counters_cache.owner_uid = ttrss_feed_categories.owner_uid AND
 			ttrss_feed_categories.owner_uid = ?");
 		$sth->execute([$_SESSION['uid']]);
@@ -172,7 +172,7 @@ class Counters {
 			FROM ttrss_feeds, ttrss_counters_cache
 			WHERE ttrss_feeds.owner_uid = ?
 				AND ttrss_counters_cache.owner_uid = ttrss_feeds.owner_uid
-				AND ttrss_counters_cache.feed_id = id");
+				AND ttrss_counters_cache.feed_id = ttrss_feeds.id");
 		$sth->execute([$_SESSION['uid']]);
 
 		while ($line = $sth->fetch()) {
diff --git a/classes/feeds.php b/classes/feeds.php
index 6b499e65c..fc2551f5e 100755
--- a/classes/feeds.php
+++ b/classes/feeds.php
@@ -231,7 +231,7 @@ class Feeds extends Handler_Protected {
 				++$headlines_count;
 
 				if (!get_pref('SHOW_CONTENT_PREVIEW')) {
-					$line["content_preview"] = null;
+					$line["content_preview"] = "";
 				} else {
 					$line["content_preview"] =  "— " . truncate_string(strip_tags($line["content"]), 250);