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new 5c13e26 Add count_time aggregation usage doc (#73)
5c13e26 is described below
commit 5c13e264ceb92e3f653cdf5a18c5d4f549816d80
Author: Beyyes <[email protected]>
AuthorDate: Fri Aug 25 18:05:26 2023 +0800
Add count_time aggregation usage doc (#73)
---
.../stage/Operators-Functions/Aggregation.md | 143 ++++++++++++++++++---
.../stage/Operators-Functions/Aggregation.md | 143 ++++++++++++++++++---
.../stage/Operators-Functions/Aggregation.md | 117 ++++++++++++++++-
.../stage/Operators-Functions/Aggregation.md | 113 ++++++++++++++++
4 files changed, 482 insertions(+), 34 deletions(-)
diff --git a/src/UserGuide/Master/stage/Operators-Functions/Aggregation.md
b/src/UserGuide/Master/stage/Operators-Functions/Aggregation.md
index 332e2cd..201fa0b 100644
--- a/src/UserGuide/Master/stage/Operators-Functions/Aggregation.md
+++ b/src/UserGuide/Master/stage/Operators-Functions/Aggregation.md
@@ -27,21 +27,23 @@ All aggregate functions except `COUNT()`, `COUNT_IF()`
ignore null values and re
The aggregate functions supported by IoTDB are as follows:
-| Function Name | Description
| Allowed Input Series Data Types | Required Attributes
| Output Series Data Type |
-| ------------- | ------------------------------------------------------------
| ------------------------------- |
------------------------------------------------------------ |
----------------------------------- |
-| SUM | Summation.
| INT32 INT64 FLOAT DOUBLE | /
| DOUBLE |
-| COUNT | Counts the number of data points.
| All data types | /
| INT |
-| AVG | Average.
| INT32 INT64 FLOAT DOUBLE | /
| DOUBLE |
-| EXTREME | Finds the value with the largest absolute value. Returns a
positive value if the maximum absolute value of positive and negative values is
equal. | INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
-| MAX_VALUE | Find the maximum value.
| INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
-| MIN_VALUE | Find the minimum value.
| INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
-| FIRST_VALUE | Find the value with the smallest timestamp.
| All data types | /
| Consistent with input data type |
-| LAST_VALUE | Find the value with the largest timestamp.
| All data types | /
| Consistent with input data type |
-| MAX_TIME | Find the maximum timestamp.
| All data Types | /
| Timestamp |
-| MIN_TIME | Find the minimum timestamp.
| All data Types | /
| Timestamp |
-| COUNT_IF | Find the number of data points that continuously meet a
given condition and the number of data points that meet the condition
(represented by keep) meet the specified threshold. | BOOLEAN
| `[keep >=/>/=/!=/</<=]threshold`：The specified threshold or threshold
condition, it is equivalent to `keep >= threshold` if `threshold` is used
alone, type of `threshold` is `INT64` `ignoreNull`：Optional, default value is
`true`；If the value is `true`, null va [...]
-| TIME_DURATION | Find the difference between the timestamp of the largest
non-null value and the timestamp of the smallest non-null value in a column |
All data Types | /
| INT64 |
-| MODE | Find the mode. Note: 1.Having too many different values in
the input series risks a memory exception; 2.If all the elements have the same
number of occurrences, that is no Mode, return the value with earliest time;
3.If there are many Modes, return the Mode with earliest time. | All data Types
| /
| Consistent with the input data type |
+| Function Name | Description
| Allowed Input Series Data Types | Required Attributes
| Output Series Data Type |
+| ------------- | ------------------------------------------------------------
|-----------------------------------------------------|
------------------------------------------------------------ |
----------------------------------- |
+| SUM | Summation.
| INT32 INT64 FLOAT DOUBLE | /
| DOUBLE |
+| COUNT | Counts the number of data points.
| All data types | /
| INT |
+| AVG | Average.
| INT32 INT64 FLOAT DOUBLE | /
| DOUBLE |
+| EXTREME | Finds the value with the largest absolute value. Returns a
positive value if the maximum absolute value of positive and negative values is
equal. | INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data
type |
+| MAX_VALUE | Find the maximum value.
| INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
+| MIN_VALUE | Find the minimum value.
| INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
+| FIRST_VALUE | Find the value with the smallest timestamp.
| All data types | /
| Consistent with input data type |
+| LAST_VALUE | Find the value with the largest timestamp.
| All data types | /
| Consistent with input data type |
+| MAX_TIME | Find the maximum timestamp.
| All data Types | /
| Timestamp |
+| MIN_TIME | Find the minimum timestamp.
| All data Types | /
| Timestamp |
+| COUNT_IF | Find the number of data points that continuously meet a
given condition and the number of data points that meet the condition
(represented by keep) meet the specified threshold. | BOOLEAN
| `[keep >=/>/=/!=/</<=]threshold`：The specified
threshold or threshold condition, it is equivalent to `keep >= threshold` if
`threshold` is used alone, type of `threshold` is `INT64`
`ignoreNull`：Optional, default value is `true`；If the valu [...]
+| TIME_DURATION | Find the difference between the timestamp of the largest
non-null value and the timestamp of the smallest non-null value in a column |
All data Types | /
| INT64 |
+| MODE | Find the mode. Note: 1.Having too many different values in
the input series risks a memory exception; 2.If all the elements have the same
number of occurrences, that is no Mode, return the value with earliest time;
3.If there are many Modes, return the Mode with earliest time. | All data Types
| /
| Consistent with the input data type |
+| COUNT_TIME | The number of timestamps in the query data set. When used
with `align by device`, the result is the number of timestamps in the data set
per device.
| All data
Types, the input parameter can only be `*` | /
[...]
+
## COUNT
@@ -179,4 +181,113 @@ Result:
| 1677570933|
+----------------------------+
```
-> Note: Returns 0 if there is only one data point, or null if the data point
is null.
\ No newline at end of file
+> Note: Returns 0 if there is only one data point, or null if the data point
is null.
+
+## COUNT_TIME
+### Grammar
+```sql
+ count_time(*)
+```
+### Example
+#### raw data
+```
++----------+-------------+-------------+-------------+-------------+
+| Time|root.db.d1.s1|root.db.d1.s2|root.db.d2.s1|root.db.d2.s2|
++----------+-------------+-------------+-------------+-------------+
+| 0| 0| null| null| 0|
+| 1| null| 1| 1| null|
+| 2| null| 2| 2| null|
+| 4| 4| null| null| 4|
+| 5| 5| 5| 5| 5|
+| 7| null| 7| 7| null|
+| 8| 8| 8| 8| 8|
+| 9| null| 9| null| null|
++----------+-------------+-------------+-------------+-------------+
+```
+#### Insert sql
+```sql
+CREATE DATABASE root.db;
+CREATE TIMESERIES root.db.d1.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d1.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+INSERT INTO root.db.d1(time, s1) VALUES(0, 0), (4,4), (5,5), (8,8);
+INSERT INTO root.db.d1(time, s2) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8),
(9,9);
+INSERT INTO root.db.d2(time, s1) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8);
+INSERT INTO root.db.d2(time, s2) VALUES(0, 0), (4,4), (5,5), (8,8);
+```
+
+Query-Example - 1:
+```sql
+select count_time(*) from root.db.**
+```
+
+Result
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+Query-Example - 2:
+```sql
+select count_time(*) from root.db.d1, root.db.d2
+```
+
+Result
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+Query-Example - 3:
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms)
+```
+
+Result
+```
++-----------------------------+-------------+
+| Time|count_time(*)|
++-----------------------------+-------------+
+|1970-01-01T08:00:00.000+08:00| 2|
+|1970-01-01T08:00:00.002+08:00| 1|
+|1970-01-01T08:00:00.004+08:00| 2|
+|1970-01-01T08:00:00.006+08:00| 1|
+|1970-01-01T08:00:00.008+08:00| 2|
++-----------------------------+-------------+
+```
+
+Query-Example - 4:
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms) align by device
+```
+
+Result
+```
++-----------------------------+----------+-------------+
+| Time| Device|count_time(*)|
++-----------------------------+----------+-------------+
+|1970-01-01T08:00:00.000+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.000+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d2| 1|
++-----------------------------+----------+-------------+
+```
+
+> Note:
+> 1. The parameter in count_time can only be *.
+> 2. Count_time aggregation cannot be used with other aggregation functions.
+> 3. Count_time aggregation used with having statement is not supported, and
count_time aggregation can not appear in the having statement.
+> 4. Count_time does not support use with group by level, group by tag.
\ No newline at end of file
diff --git a/src/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
b/src/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
index 332e2cd..385aefc 100644
--- a/src/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
+++ b/src/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
@@ -27,21 +27,23 @@ All aggregate functions except `COUNT()`, `COUNT_IF()`
ignore null values and re
The aggregate functions supported by IoTDB are as follows:
-| Function Name | Description
| Allowed Input Series Data Types | Required Attributes
| Output Series Data Type |
-| ------------- | ------------------------------------------------------------
| ------------------------------- |
------------------------------------------------------------ |
----------------------------------- |
-| SUM | Summation.
| INT32 INT64 FLOAT DOUBLE | /
| DOUBLE |
-| COUNT | Counts the number of data points.
| All data types | /
| INT |
-| AVG | Average.
| INT32 INT64 FLOAT DOUBLE | /
| DOUBLE |
-| EXTREME | Finds the value with the largest absolute value. Returns a
positive value if the maximum absolute value of positive and negative values is
equal. | INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
-| MAX_VALUE | Find the maximum value.
| INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
-| MIN_VALUE | Find the minimum value.
| INT32 INT64 FLOAT DOUBLE | /
| Consistent with the input data type |
-| FIRST_VALUE | Find the value with the smallest timestamp.
| All data types | /
| Consistent with input data type |
-| LAST_VALUE | Find the value with the largest timestamp.
| All data types | /
| Consistent with input data type |
-| MAX_TIME | Find the maximum timestamp.
| All data Types | /
| Timestamp |
-| MIN_TIME | Find the minimum timestamp.
| All data Types | /
| Timestamp |
-| COUNT_IF | Find the number of data points that continuously meet a
given condition and the number of data points that meet the condition
(represented by keep) meet the specified threshold. | BOOLEAN
| `[keep >=/>/=/!=/</<=]threshold`：The specified threshold or threshold
condition, it is equivalent to `keep >= threshold` if `threshold` is used
alone, type of `threshold` is `INT64` `ignoreNull`：Optional, default value is
`true`；If the value is `true`, null va [...]
-| TIME_DURATION | Find the difference between the timestamp of the largest
non-null value and the timestamp of the smallest non-null value in a column |
All data Types | /
| INT64 |
-| MODE | Find the mode. Note: 1.Having too many different values in
the input series risks a memory exception; 2.If all the elements have the same
number of occurrences, that is no Mode, return the value with earliest time;
3.If there are many Modes, return the Mode with earliest time. | All data Types
| /
| Consistent with the input data type |
+| Function Name | Description
| Allowed Input
Series Data Types | Required Attributes
[...]
+| -------------
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------
[...]
+| SUM | Summation.
| INT32 INT64 FLOAT
DOUBLE | /
[...]
+| COUNT | Counts the number of data points.
| All data types
| /
[...]
+| AVG | Average.
| INT32 INT64 FLOAT
DOUBLE | /
[...]
+| EXTREME | Finds the value with the largest absolute value. Returns a
positive value if the maximum absolute value of positive and negative values is
equal.
| INT32 INT64
FLOAT DOUBLE | /
[...]
+| MAX_VALUE | Find the maximum value.
| INT32 INT64 FLOAT
DOUBLE | /
[...]
+| MIN_VALUE | Find the minimum value.
| INT32 INT64 FLOAT
DOUBLE | /
[...]
+| FIRST_VALUE | Find the value with the smallest timestamp.
| All data types
| /
[...]
+| LAST_VALUE | Find the value with the largest timestamp.
| All data types
| /
[...]
+| MAX_TIME | Find the maximum timestamp.
| All data Types
| /
[...]
+| MIN_TIME | Find the minimum timestamp.
| All data Types
| /
[...]
+| COUNT_IF | Find the number of data points that continuously meet a
given condition and the number of data points that meet the condition
(represented by keep) meet the specified threshold.
|
BOOLEAN | `[keep
>=/>/=/!=/</<=]threshold`：The specified threshold or threshold condition, it is
equivalent to `keep >= threshold` if `threshold` i [...]
+| TIME_DURATION | Find the difference between the timestamp of the largest
non-null value and the timestamp of the smallest non-null value in a column
| All data
Types | /
[...]
+| MODE | Find the mode. Note: 1.Having too many different values in
the input series risks a memory exception; 2.If all the elements have the same
number of occurrences, that is no Mode, return the value with earliest time;
3.If there are many Modes, return the Mode with earliest time. | All data Types
| /
[...]
+| COUNT_TIME | The number of timestamps in the query data set. When used
with `align by device`, the result is the number of timestamps in the data set
per device.
| All data
Types, the input parameter can only be `*` | /
[...]
+
## COUNT
@@ -179,4 +181,113 @@ Result:
| 1677570933|
+----------------------------+
```
-> Note: Returns 0 if there is only one data point, or null if the data point
is null.
\ No newline at end of file
+> Note: Returns 0 if there is only one data point, or null if the data point
is null.
+
+## COUNT_TIME
+### Grammar
+```sql
+ count_time(*)
+```
+### Example
+#### raw data
+```
++----------+-------------+-------------+-------------+-------------+
+| Time|root.db.d1.s1|root.db.d1.s2|root.db.d2.s1|root.db.d2.s2|
++----------+-------------+-------------+-------------+-------------+
+| 0| 0| null| null| 0|
+| 1| null| 1| 1| null|
+| 2| null| 2| 2| null|
+| 4| 4| null| null| 4|
+| 5| 5| 5| 5| 5|
+| 7| null| 7| 7| null|
+| 8| 8| 8| 8| 8|
+| 9| null| 9| null| null|
++----------+-------------+-------------+-------------+-------------+
+```
+#### Insert sql
+```sql
+CREATE DATABASE root.db;
+CREATE TIMESERIES root.db.d1.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d1.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+INSERT INTO root.db.d1(time, s1) VALUES(0, 0), (4,4), (5,5), (8,8);
+INSERT INTO root.db.d1(time, s2) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8),
(9,9);
+INSERT INTO root.db.d2(time, s1) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8);
+INSERT INTO root.db.d2(time, s2) VALUES(0, 0), (4,4), (5,5), (8,8);
+```
+
+Query-Example - 1:
+```sql
+select count_time(*) from root.db.**
+```
+
+Result
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+Query-Example - 2:
+```sql
+select count_time(*) from root.db.d1, root.db.d2
+```
+
+Result
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+Query-Example - 3:
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms)
+```
+
+Result
+```
++-----------------------------+-------------+
+| Time|count_time(*)|
++-----------------------------+-------------+
+|1970-01-01T08:00:00.000+08:00| 2|
+|1970-01-01T08:00:00.002+08:00| 1|
+|1970-01-01T08:00:00.004+08:00| 2|
+|1970-01-01T08:00:00.006+08:00| 1|
+|1970-01-01T08:00:00.008+08:00| 2|
++-----------------------------+-------------+
+```
+
+Query-Example - 4:
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms) align by device
+```
+
+Result
+```
++-----------------------------+----------+-------------+
+| Time| Device|count_time(*)|
++-----------------------------+----------+-------------+
+|1970-01-01T08:00:00.000+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.000+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d2| 1|
++-----------------------------+----------+-------------+
+```
+
+> Note:
+> 1. The parameter in count_time can only be *.
+> 2. Count_time aggregation cannot be used with other aggregation functions.
+> 3. Count_time aggregation used with having statement is not supported, and
count_time aggregation can not appear in the having statement.
+> 4. Count_time does not support use with group by level, group by tag.
\ No newline at end of file
diff --git a/src/zh/UserGuide/Master/stage/Operators-Functions/Aggregation.md
b/src/zh/UserGuide/Master/stage/Operators-Functions/Aggregation.md
index 5c689b6..7d4366e 100644
--- a/src/zh/UserGuide/Master/stage/Operators-Functions/Aggregation.md
+++ b/src/zh/UserGuide/Master/stage/Operators-Functions/Aggregation.md
@@ -40,8 +40,11 @@ IoTDB 支持的聚合函数如下：
| MAX_TIME | 求最大时间戳。
| 所有类型 | 无
| Timestamp |
| MIN_TIME | 求最小时间戳。
| 所有类型 | 无
| Timestamp |
| COUNT_IF | 求数据点连续满足某一给定条件，且满足条件的数据点个数（用keep表示）满足指定阈值的次数。
| BOOLEAN | `[keep
>=/>/=/!=/</<=]threshold`：被指定的阈值或阈值条件，若只使用`threshold`则等价于`keep >=
threshold`,`threshold`类型为`INT64` <br>
`ignoreNull`：可选，默认为`true`；为`true`表示忽略null值，即如果中间出现null值，直接忽略，不会打断连续性；为`false`表示不忽略null值，即如果中间出现null值，会打断连续性
| INT64 |
-| TIME_DURATION | 求某一列最大一个不为NULL的值所在时间戳与最小一个不为NULL的值所在时间戳的时间戳差
| 所有类型 | 无
| INT64 |
-| MODE | 求众数。注意：<br>1.输入序列的不同值个数过多时会有内存异常风险;
<br>2.如果所有元素出现的频次相同，即没有众数，则返回对应时间戳最小的值; <br>3.如果有多个众数，则返回对应时间戳最小的众数。 | 所有类型
| 无
|
与输入类型一致 |
+| TIME_DURATION | 求某一列最大一个不为NULL的值所在时间戳与最小一个不为NULL的值所在时间戳的时间戳差
| 所有类型 | 无
| INT64 |
+| MODE | 求众数。注意：<br>1.输入序列的不同值个数过多时会有内存异常风险;
<br>2.如果所有元素出现的频次相同，即没有众数，则返回对应时间戳最小的值; <br>3.如果有多个众数，则返回对应时间戳最小的众数。 | 所有类型
| 无
|
与输入类型一致 |
+| COUNT_TIME | 查询结果集的时间戳的数量。与 align by device 搭配使用时，得到的结果是每个设备的结果集的时间戳的数量。
| 所有类型，输入参数只能为* | 无 |
INT64 |
+
+
## COUNT_IF
### 语法
@@ -160,3 +163,113 @@ select time_duration(s1) from root.db.d1
+----------------------------+
```
> 注：若数据点只有一个，则返回0，若数据点为null，则返回null。
+
+## COUNT_TIME
+### 语法
+```sql
+ count_time(*)
+```
+### 使用示例
+#### 准备数据
+```
++----------+-------------+-------------+-------------+-------------+
+| Time|root.db.d1.s1|root.db.d1.s2|root.db.d2.s1|root.db.d2.s2|
++----------+-------------+-------------+-------------+-------------+
+| 0| 0| null| null| 0|
+| 1| null| 1| 1| null|
+| 2| null| 2| 2| null|
+| 4| 4| null| null| 4|
+| 5| 5| 5| 5| 5|
+| 7| null| 7| 7| null|
+| 8| 8| 8| 8| 8|
+| 9| null| 9| null| null|
++----------+-------------+-------------+-------------+-------------+
+```
+#### 写入语句
+```sql
+CREATE DATABASE root.db;
+CREATE TIMESERIES root.db.d1.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d1.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+INSERT INTO root.db.d1(time, s1) VALUES(0, 0), (4,4), (5,5), (8,8);
+INSERT INTO root.db.d1(time, s2) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8),
(9,9);
+INSERT INTO root.db.d2(time, s1) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8);
+INSERT INTO root.db.d2(time, s2) VALUES(0, 0), (4,4), (5,5), (8,8);
+```
+
+查询示例1：
+```sql
+select count_time(*) from root.db.**
+```
+
+输出
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+查询示例2：
+```sql
+select count_time(*) from root.db.d1, root.db.d2
+```
+
+输出
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+查询示例3：
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms)
+```
+
+输出
+```
++-----------------------------+-------------+
+| Time|count_time(*)|
++-----------------------------+-------------+
+|1970-01-01T08:00:00.000+08:00| 2|
+|1970-01-01T08:00:00.002+08:00| 1|
+|1970-01-01T08:00:00.004+08:00| 2|
+|1970-01-01T08:00:00.006+08:00| 1|
+|1970-01-01T08:00:00.008+08:00| 2|
++-----------------------------+-------------+
+```
+
+查询示例4：
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms) align by device
+```
+
+输出
+```
++-----------------------------+----------+-------------+
+| Time| Device|count_time(*)|
++-----------------------------+----------+-------------+
+|1970-01-01T08:00:00.000+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.000+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d2| 1|
++-----------------------------+----------+-------------+
+
+```
+
+> 注：
+> 1. count_time里的表达式只能为*。
+> 2. count_time不能和其他的聚合函数一起使用。
+> 3. having语句里不支持使用count_time, 使用count_time聚合函数时不支持使用having语句。
+> 4. count_time不支持与group by level, group by tag一起使用。
diff --git a/src/zh/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
b/src/zh/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
index 5c689b6..dcf3def 100644
--- a/src/zh/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
+++ b/src/zh/UserGuide/V1.2.x/stage/Operators-Functions/Aggregation.md
@@ -42,6 +42,9 @@ IoTDB 支持的聚合函数如下：
| COUNT_IF | 求数据点连续满足某一给定条件，且满足条件的数据点个数（用keep表示）满足指定阈值的次数。
| BOOLEAN | `[keep
>=/>/=/!=/</<=]threshold`：被指定的阈值或阈值条件，若只使用`threshold`则等价于`keep >=
threshold`,`threshold`类型为`INT64` <br>
`ignoreNull`：可选，默认为`true`；为`true`表示忽略null值，即如果中间出现null值，直接忽略，不会打断连续性；为`false`表示不忽略null值，即如果中间出现null值，会打断连续性
| INT64 |
| TIME_DURATION | 求某一列最大一个不为NULL的值所在时间戳与最小一个不为NULL的值所在时间戳的时间戳差
| 所有类型 | 无
| INT64 |
| MODE | 求众数。注意：<br>1.输入序列的不同值个数过多时会有内存异常风险;
<br>2.如果所有元素出现的频次相同，即没有众数，则返回对应时间戳最小的值; <br>3.如果有多个众数，则返回对应时间戳最小的众数。 | 所有类型
| 无
|
与输入类型一致 |
+| COUNT_TIME | 查询结果集的时间戳的数量。与 align by device 搭配使用时，得到的结果是每个设备的结果集的时间戳的数量。
| 所有类型，输入参数只能为* | 无 |
INT64 |
+
+
## COUNT_IF
### 语法
@@ -160,3 +163,113 @@ select time_duration(s1) from root.db.d1
+----------------------------+
```
> 注：若数据点只有一个，则返回0，若数据点为null，则返回null。
+
+## COUNT_TIME
+### 语法
+```sql
+ count_time(*)
+```
+### 使用示例
+#### 准备数据
+```
++----------+-------------+-------------+-------------+-------------+
+| Time|root.db.d1.s1|root.db.d1.s2|root.db.d2.s1|root.db.d2.s2|
++----------+-------------+-------------+-------------+-------------+
+| 0| 0| null| null| 0|
+| 1| null| 1| 1| null|
+| 2| null| 2| 2| null|
+| 4| 4| null| null| 4|
+| 5| 5| 5| 5| 5|
+| 7| null| 7| 7| null|
+| 8| 8| 8| 8| 8|
+| 9| null| 9| null| null|
++----------+-------------+-------------+-------------+-------------+
+```
+#### 写入语句
+```sql
+CREATE DATABASE root.db;
+CREATE TIMESERIES root.db.d1.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d1.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s1 WITH DATATYPE=INT32, ENCODING=PLAIN;
+CREATE TIMESERIES root.db.d2.s2 WITH DATATYPE=INT32, ENCODING=PLAIN;
+INSERT INTO root.db.d1(time, s1) VALUES(0, 0), (4,4), (5,5), (8,8);
+INSERT INTO root.db.d1(time, s2) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8),
(9,9);
+INSERT INTO root.db.d2(time, s1) VALUES(1, 1), (2,2), (5,5), (7,7), (8,8);
+INSERT INTO root.db.d2(time, s2) VALUES(0, 0), (4,4), (5,5), (8,8);
+```
+
+查询示例1：
+```sql
+select count_time(*) from root.db.**
+```
+
+输出
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+查询示例2：
+```sql
+select count_time(*) from root.db.d1, root.db.d2
+```
+
+输出
+```
++-------------+
+|count_time(*)|
++-------------+
+| 8|
++-------------+
+```
+
+查询示例3：
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms)
+```
+
+输出
+```
++-----------------------------+-------------+
+| Time|count_time(*)|
++-----------------------------+-------------+
+|1970-01-01T08:00:00.000+08:00| 2|
+|1970-01-01T08:00:00.002+08:00| 1|
+|1970-01-01T08:00:00.004+08:00| 2|
+|1970-01-01T08:00:00.006+08:00| 1|
+|1970-01-01T08:00:00.008+08:00| 2|
++-----------------------------+-------------+
+```
+
+查询示例4：
+```sql
+select count_time(*) from root.db.** group by([0, 10), 2ms) align by device
+```
+
+输出
+```
++-----------------------------+----------+-------------+
+| Time| Device|count_time(*)|
++-----------------------------+----------+-------------+
+|1970-01-01T08:00:00.000+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d1| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d1| 2|
+|1970-01-01T08:00:00.000+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.002+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.004+08:00|root.db.d2| 2|
+|1970-01-01T08:00:00.006+08:00|root.db.d2| 1|
+|1970-01-01T08:00:00.008+08:00|root.db.d2| 1|
++-----------------------------+----------+-------------+
+
+```
+
+> 注：
+> 1. count_time里的表达式只能为*。
+> 2. count_time不能和其他的聚合函数一起使用。
+> 3. having语句里不支持使用count_time, 使用count_time聚合函数时不支持使用having语句。
+> 4. count_time不支持与group by level, group by tag一起使用。
