diff --git a/include/dba.php b/include/dba.php
index 17c62b8144..9d828f8b44 100644
--- a/include/dba.php
+++ b/include/dba.php
@@ -1015,7 +1015,7 @@ class dba {
 		$commands = [];
 
 		// Create a key for the loop prevention
-		$key = $table . ':' . implode(':', array_keys($conditions)) . ':' . implode(':', $conditions);
+		$key = $table . ':' . json_encode($conditions);
 
 		// We quit when this key already exists in the callstack.
 		if (isset($callstack[$key])) {
@@ -1042,7 +1042,7 @@ class dba {
 			$rel_def = array_values(self::$relation[$table])[0];
 
 			// Create a key for preventing double queries
-			$qkey = $field . '-' . $table . ':' . implode(':', array_keys($conditions)) . ':' . implode(':', $conditions);
+			$qkey = $field . '-' . $table . ':' . json_encode($conditions);
 
 			// When the search field is the relation field, we don't need to fetch the rows
 			// This is useful when the leading record is already deleted in the frontend but the rest is done in the backend