From f7536c7e889a0a69a8ba1b72ac86556dbbf4f8db Mon Sep 17 00:00:00 2001
From: cooper-lzy <78672629+cooper-lzy@users.noreply.github.com>
Date: Fri, 18 Feb 2022 11:09:52 +0800
Subject: [PATCH] Update 3.alter-tag.md

---
 docs-2.0/3.ngql-guide/10.tag-statements/3.alter-tag.md | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/docs-2.0/3.ngql-guide/10.tag-statements/3.alter-tag.md b/docs-2.0/3.ngql-guide/10.tag-statements/3.alter-tag.md
index 1b17fc7a2a8..f9b634a9601 100644
--- a/docs-2.0/3.ngql-guide/10.tag-statements/3.alter-tag.md
+++ b/docs-2.0/3.ngql-guide/10.tag-statements/3.alter-tag.md
@@ -14,9 +14,7 @@
 ALTER TAG <tag_name>
     <alter_definition> [[, alter_definition] ...]
     [ttl_definition [, ttl_definition] ... ]
-    [COMMENT '<comment>']
-    [NOT NULL]
-    [DEFAULT <defalut_value>];
+    [COMMENT '<comment>'];
 
 alter_definition:
 | ADD    (prop_name data_type [NULL | NOT NULL] [DEFAULT <default_value>] [COMMENT '<comment>'])