diff --git a/mod/mod-mysql.c b/mod/mod-mysql.c
index bc32edd9..3ffe948e 100644
--- a/mod/mod-mysql.c
+++ b/mod/mod-mysql.c
@@ -34,7 +34,7 @@
 
 struct param_data_t
 {
-	my_bool is_null;
+	int is_null;
 	union
 	{
 		my_ulonglong llv;