diff --git a/documentation20/en/04.model/docs.md b/documentation20/en/04.model/docs.md
index 1bf6c6787846b65ec9b56b65b80470cad2224756..08d952d317e30ef91dad32333c9abb0e646b8e48 100644
--- a/documentation20/en/04.model/docs.md
+++ b/documentation20/en/04.model/docs.md
@@ -26,6 +26,7 @@ Replace the database operating in the current connection with “power”, other
 
 - Any table or STable belongs to a database. Before creating a table, a database must be created first.
 - Tables in two different databases cannot be JOIN.
+- You need to specify a timestamp when creating and inserting records, or querying history records.
 
 ## <a class="anchor" id="create-stable"></a> Create a STable