diff --git a/backend/redis/similarity.go b/backend/redis/similarity.go
index ad6169e..99cd583 100644
--- a/backend/redis/similarity.go
+++ b/backend/redis/similarity.go
@@ -141,7 +141,11 @@ func (s *SimilarityService) FindSimilarPosts(ctx context.Context, filter *analog
 		err = s.idKeysCache.get(ctx, idKey, &idKeyHashesString)
 
 		// split string to list
-		idKeyHashes := strings.Split(idKeyHashesString, delimiter)
+		var idKeyHashes []string
+
+		if idKeyHashesString != "" {
+			idKeyHashes = strings.Split(idKeyHashesString, delimiter)
+		}
 
 		// if key already exists in slice, no more to do
 		for _, h := range idKeyHashes {
@@ -192,7 +196,11 @@ func (s *SimilarityService) DeletePost(ctx context.Context, id int) error {
 		}
 
 		// split string to list
-		idKeyHashes := strings.Split(idKeyHashesString, delimiter)
+		var idKeyHashes []string
+
+		if idKeyHashesString != "" {
+			idKeyHashes = strings.Split(idKeyHashesString, delimiter)
+		}
 
 		// for all hashes, remove from posts cache
 		for _, hash := range idKeyHashes {
diff --git a/backend/weaviate/weaviate.go b/backend/weaviate/weaviate.go
index 3ea72f0..a6cb0ad 100644
--- a/backend/weaviate/weaviate.go
+++ b/backend/weaviate/weaviate.go
@@ -101,10 +101,12 @@ func (db *DB) startTrace(ctx context.Context, spanName string, opts ...trace.Spa
 	dbSystem := attribute.String("db.system", "weaviate")
 	dbName := attribute.String("db.name", "pictures")
 	serverAddress := attribute.String("server.address", db.host)
+
+	attributes := trace.WithAttributes(dbSystem, dbName, serverAddress)
 	spanKind := trace.WithSpanKind(trace.SpanKindClient)
 
-	opts = append(opts, dbSystem, dbName, serverAddress, spanKind)
+	opts = append(opts, attributes, spanKind)
 
-	return db.tracer.Tracer.Start(ctx, spanName, opts)
+	return db.tracer.Tracer.Start(ctx, spanName, opts...)
 
 }