diff --git a/website/docs/r/sql_database_instance.html.markdown b/website/docs/r/sql_database_instance.html.markdown
index 7c8833f87a2..63d98de4cad 100644
--- a/website/docs/r/sql_database_instance.html.markdown
+++ b/website/docs/r/sql_database_instance.html.markdown
@@ -217,7 +217,7 @@ includes an up-to-date reference of supported versions.
     is not provided, the provider project is used.
 
 * `replica_configuration` - (Optional) The configuration for replication. The
-    configuration is detailed below.
+    configuration is detailed below. Valid only for MySQL instances.
     
 * `root_password` - (Optional) Initial root password. Required for MS SQL Server, ignored by MySQL and PostgreSQL.