diff --git a/libs/sql/sql_query.h b/libs/sql/sql_query.h
index 0a5d150..5bb09d9 100644
--- a/libs/sql/sql_query.h
+++ b/libs/sql/sql_query.h
@@ -26,6 +26,7 @@
 #include <QSqlError>
 #include <QSqlQuery>
 #include <QVariant>
+#include <functional>
 
 
 namespace QAD {