diff --git a/docs-2.0/3.ngql-guide/6.functions-and-expressions/15.aggregating.md b/docs-2.0/3.ngql-guide/6.functions-and-expressions/15.aggregating.md
index 02ce125728f..ff86d1cb4d7 100644
--- a/docs-2.0/3.ngql-guide/6.functions-and-expressions/15.aggregating.md
+++ b/docs-2.0/3.ngql-guide/6.functions-and-expressions/15.aggregating.md
@@ -287,6 +287,44 @@ nebula> LOOKUP ON player \
 
 ```
 
+## std()
+
+std() 返回参数的总体标准差。
+
+语法：`std(<expression>)`
+
+- 返回类型：double。
+
+示例：
+
+```ngql
+nebula> MATCH (v:player) RETURN std(v.player.age);
++-------------------+
+| std(v.player.age) |
++-------------------+
+| 6.423895701687502 |
++-------------------+
+```
+
+## sum()
+
+sum() 返回参数的和。
+
+语法：`sum(<expression>)`
+
+- 返回类型：与原参数相同。
+
+示例：
+
+```ngql
+nebula> MATCH (v:player) RETURN sum(v.player.age);
++-------------------+
+| sum(v.player.age) |
++-------------------+
+| 1698              |
++-------------------+
+```
+
 ## 聚合示例
 
 ```ngql
diff --git a/docs-2.0/3.ngql-guide/6.functions-and-expressions/16.type-conversion.md b/docs-2.0/3.ngql-guide/6.functions-and-expressions/16.type-conversion.md
index 23dfb2c5463..1a4e2433fe9 100644
--- a/docs-2.0/3.ngql-guide/6.functions-and-expressions/16.type-conversion.md
+++ b/docs-2.0/3.ngql-guide/6.functions-and-expressions/16.type-conversion.md
@@ -150,41 +150,3 @@ nebula> YIELD hash(toLower("HELLO NEBULA"));
 +-------------------------------+
 ```
 
-
-## std()
-
-std() 返回参数的总体标准差。
-
-语法：`std(<expression>)`
-
-- 返回类型：double。
-
-示例：
-
-```ngql
-nebula> MATCH (v:player) RETURN std(v.player.age);
-+-------------------+
-| std(v.player.age) |
-+-------------------+
-| 6.423895701687502 |
-+-------------------+
-```
-
-## sum()
-
-sum() 返回参数的和。
-
-语法：`sum(<expression>)`
-
-- 返回类型：与原参数相同。
-
-示例：
-
-```ngql
-nebula> MATCH (v:player) RETURN sum(v.player.age);
-+-------------------+
-| sum(v.player.age) |
-+-------------------+
-| 1698              |
-+-------------------+
-```
\ No newline at end of file