diff --git a/docs/en/14-reference/12-config/index.md b/docs/en/14-reference/12-config/index.md
index c88772cc9e..7075dc771e 100644
--- a/docs/en/14-reference/12-config/index.md
+++ b/docs/en/14-reference/12-config/index.md
@@ -179,9 +179,10 @@ The parameters described in this document by the effect that they have on the sy
 | Attribute     | Description                             |
 | -------- | -------------------------------- |
 | Applicable | Server only                     |
-| Meaning   | count()/hyperloglog() return value or not if the result data is NULL |
+| Meaning   | count()/hyperloglog() return value or not if the input data is empty or NULL |
 | Vlue Range | 0：Return empty line，1：Return 0       |
 | Default   | 1                            |
+| Notes | When this parameter is setting to 1, for queries containing GROUP BY, PARTITION BY and INTERVAL clause, and input data in certain groups or windows is empty or NULL, the corresponding groups or windows have no return values |
 
 ### maxNumOfDistinctRes
 
diff --git a/docs/zh/14-reference/12-config/index.md b/docs/zh/14-reference/12-config/index.md
index c903ad7df6..eed8b9ca7d 100644
--- a/docs/zh/14-reference/12-config/index.md
+++ b/docs/zh/14-reference/12-config/index.md
@@ -192,14 +192,15 @@ taos --dump-config
 | 取值范围 | 0 表示包含函数名，1 表示不包含函数名。      |
 | 缺省值   | 0                            |
 
-### countAlwaysReturnValue 
+### countAlwaysReturnValue
 
 | 属性     | 说明                             |
 | -------- | -------------------------------- |
 | 适用范围 | 仅服务端适用                     |
-| 含义     | count/hyperloglog函数在数据为空或者NULL的情况下是否返回值 |
+| 含义     | count/hyperloglog函数在输入数据为空或者NULL的情况下是否返回值 |
 | 取值范围 | 0：返回空行，1：返回 0       |
 | 缺省值   | 1                            |
+| 补充说明 | 该参数设置为 1 时，如果查询中含有 GROUP BY，PARTITION BY 以及 INTERVAL 子句且相应的组或窗口内数据为空或者NULL， 对应的组或窗口将不返回查询结果 |
 
 ## 区域相关