update deltasum.md

docs/zh/sql-reference/aggregate-functions/reference/deltasum.md

@@ -4,20 +4,66 @@ toc_priority: 141
 
 # deltaSum {#agg_functions-deltasum}
 
+计算连续行之间的差值和。如果差值为负，则忽略。
+
 **语法**
 
 ``` sql
 deltaSum(value)
 ```
 
-计算连续行之间的差值和。如果差值为负，则忽略。
-`value`必须是整型或浮点类型。
+**参数**
 
-示例:
+-   `value` — 必须是 [整型](../../data-types/int-uint.md) 或者 [浮点型](../../data-types/float.md) 。
 
-```sql
-select deltaSum(arrayJoin([1, 2, 3]));                  -- => 2
-select deltaSum(arrayJoin([1, 2, 3, 0, 3, 4, 2, 3]));   -- => 7
-select deltaSum(arrayJoin([2.25, 3, 4.5])); -- => 2.25
+**返回值**
+
+- `Integer` or `Float` 型的算术差值和。
+
+**示例**
+
+查询:
+
+``` sql
+SELECT deltaSum(arrayJoin([1, 2, 3]));
 ```
 
+结果:
+
+``` text
+┌─deltaSum(arrayJoin([1, 2, 3]))─┐
+│                              2 │
+└────────────────────────────────┘
+```
+
+查询:
+
+``` sql
+SELECT deltaSum(arrayJoin([1, 2, 3, 0, 3, 4, 2, 3]));
+```
+
+结果:
+
+``` text
+┌─deltaSum(arrayJoin([1, 2, 3, 0, 3, 4, 2, 3]))─┐
+│                                             7 │
+└───────────────────────────────────────────────┘
+```
+
+查询:
+
+``` sql
+SELECT deltaSum(arrayJoin([2.25, 3, 4.5]));
+```
+
+结果:
+
+``` text
+┌─deltaSum(arrayJoin([2.25, 3, 4.5]))─┐
+│                                2.25 │
+└─────────────────────────────────────┘
+```
+
+## 参见 {#see-also}
+
+-   [runningDifference](../../functions/other-functions.md#other_functions-runningdifference)