fix for #637

Author: mevdschee

api.php

@@ -9918,6 +9918,9 @@ private function getJoinsAsPathTree(array $params): PathTree
                 foreach ($params['join'] as $tableNames) {
                     $path = array();
                     foreach (explode(',', $tableNames) as $tableName) {
+                        if (!$this->reflection->hasTable($tableName)) {
+                            continue;
+                        }
                         $t = $this->reflection->getTable($tableName);
                         if ($t != null) {
                             $path[] = $t->getName();

src/Tqdev/PhpCrudApi/Record/RelationJoiner.php

@@ -62,6 +62,9 @@ private function getJoinsAsPathTree(array $params): PathTree
             foreach ($params['join'] as $tableNames) {
                 $path = array();
                 foreach (explode(',', $tableNames) as $tableName) {
+                    if (!$this->reflection->hasTable($tableName)) {
+                        continue;
+                    }
                     $t = $this->reflection->getTable($tableName);
                     if ($t != null) {
                         $path[] = $t->getName();