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Add support version to minby maxby (#784)
* fix iotdb enterprise edition to timechodb * add support version to minby and maxby * remove other changes
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‎src/UserGuide/V1.3.x/SQL-Manual/Function-and-Expression.md‎

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@@ -539,6 +539,12 @@ The aggregate functions supported by IoTDB are as follows:
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| SUM | Summation. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| COUNT | Counts the number of data points. | All data types | / | INT |
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| AVG | Average. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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STDDEV | Alias for STDDEV_SAMP. Return the sample standard deviation. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| STDDEV_POP | Return the population standard deviation. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| STDDEV_SAMP | Return the sample standard deviation. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| VARIANCE | Alias for VAR_SAMP. Return the sample variance. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| VAR_POP | Return the population variance. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| VAR_SAMP | Return the sample variance. | INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| 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 |
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| MAX_VALUE | Find the maximum value. | INT32 INT64 FLOAT DOUBLE | / | Consistent with the input data type |
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| MIN_VALUE | Find the minimum value. | INT32 INT64 FLOAT DOUBLE | / | Consistent with the input data type |
@@ -549,29 +555,11 @@ The aggregate functions supported by IoTDB are as follows:
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| 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 values are ignored, it means that if there is a null value in the middle, the value is ignored without interrupting the continuity. If the value is `true`, null values are not ignored, it means that if there are null values in the middle, continuity will be broken | INT64 |
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| 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 |
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| 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 |
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| STDDEV | Calculate the overall standard deviation of the data. Note:<br> Missing points, null points and `NaN` in the input series will be ignored.| INT32 INT64 FLOAT DOUBLE | / | DOUBLE |
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| 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 `*` | / | INT64 |
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| MAX_BY | MAX_BY(x, y) returns the value of x corresponding to the maximum value of the input y. MAX_BY(time, x) returns the timestamp when x is at its maximum value. <br> Note: Supported from version V1.3.2 | The first input x can be of any type, while the second input y must be of type INT32, INT64, FLOAT, DOUBLE, STRING, TIMESTAMP or DATE. | / | Consistent with the data type of the first input x. |
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| MIN_BY | MIN_BY(x, y) returns the value of x corresponding to the minimum value of the input y. MIN_BY(time, x) returns the timestamp when x is at its minimum value. <br> Note: Supported from version V1.3.2 | The first input x can be of any type, while the second input y must be of type INT32, INT64, FLOAT, DOUBLE, STRING, TIMESTAMP or DATE. | / | Consistent with the data type of the first input x. |
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### COUNT
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#### example
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```sql
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select count(status) from root.ln.wf01.wt01;
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```
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Result:
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```
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+-------------------------------+
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|count(root.ln.wf01.wt01.status)|
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+-------------------------------+
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| 10080|
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+-------------------------------+
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Total line number = 1
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It costs 0.016s
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```
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### COUNT_IF
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#### Grammar
@@ -800,6 +788,206 @@ Result
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> 3. Count_time aggregation used with having statement is not supported, and count_time aggregation can not appear in the having statement.
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> 4. Count_time does not support use with group by level, group by tag.
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### MAX_BY
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#### Function Definition
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`max_by(x, y)`: Returns the value of x at the timestamp where y reaches its maximum.
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- `max_by` must have two input parameters x and y.
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- The first input can be the time keyword. `max_by(time, x)` returns the timestamp when x reaches its maximum value.
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- Returns null if x is null at the timestamp where y is maximum.
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- If y achieves its maximum at multiple timestamps, returns the x value at the smallest timestamp among them.
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- Aligns with IoTDB's `max_value`: Only supports INT32, INT64, FLOAT, DOUBLE as y input. Supports all six data types as x input.
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- Inputs x and y cannot be literal values.
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#### Syntax
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```sql
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select max_by(x, y) from root.sg
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select max_by(time, x) from root.sg
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```
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#### Examples
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##### Raw Data
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```sql
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IoTDB> select * from root.test
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+-----------------------------+-----------+-----------+
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| Time|root.test.a|root.test.b|
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+-----------------------------+-----------+-----------+
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|1970-01-01T08:00:00.001+08:00| 1.0| 10.0|
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|1970-01-01T08:00:00.002+08:00| 2.0| 10.0|
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|1970-01-01T08:00:00.003+08:00| 3.0| 3.0|
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|1970-01-01T08:00:00.004+08:00| 10.0| 10.0|
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|1970-01-01T08:00:00.005+08:00| 10.0| 12.0|
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|1970-01-01T08:00:00.006+08:00| 6.0| 6.0|
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+-----------------------------+-----------+-----------+
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```
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##### Query Examples
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Get timestamp corresponding to maximum value:
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```sql
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IoTDB> select max_by(time, a), max_value(a) from root.test
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+-------------------------+------------------------+
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|max_by(Time, root.test.a)| max_value(root.test.a)|
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+-------------------------+------------------------+
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| 4| 10.0|
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+-------------------------+------------------------+
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```
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Get b value when a is maximum:
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```sql
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IoTDB> select max_by(b, a) from root.test
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+--------------------------------+
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|max_by(root.test.b, root.test.a)|
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+--------------------------------+
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| 10.0|
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+--------------------------------+
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```
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With expressions:
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```sql
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IoTDB> select max_by(b + 1, a * 2) from root.test
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+----------------------------------------+
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|max_by(root.test.b + 1, root.test.a * 2)|
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+----------------------------------------+
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| 11.0|
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+----------------------------------------+
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```
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With GROUP BY TIME clause:
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```sql
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IoTDB> select max_by(b, a) from root.test group by ([0,7),4ms)
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+-----------------------------+--------------------------------+
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| Time|max_by(root.test.b, root.test.a)|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.000+08:00| 3.0|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.004+08:00| 10.0|
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+-----------------------------+--------------------------------+
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```
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With HAVING clause:
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```sql
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IoTDB> select max_by(b, a) from root.test group by ([0,7),4ms) having max_by(b, a) > 4.0
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+-----------------------------+--------------------------------+
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| Time|max_by(root.test.b, root.test.a)|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.004+08:00| 10.0|
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+-----------------------------+--------------------------------+
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```
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With ORDER BY clause:
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```sql
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IoTDB> select max_by(b, a) from root.test group by ([0,7),4ms) order by time desc
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+-----------------------------+--------------------------------+
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| Time|max_by(root.test.b, root.test.a)|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.004+08:00| 10.0|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.000+08:00| 3.0|
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+-----------------------------+--------------------------------+
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```
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### MIN_BY
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#### Function Definition
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`min_by(x, y)`: Returns the value of x at the timestamp where y reaches its minimum.
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- `min_by` must have two input parameters x and y.
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- The first input can be the time keyword. `min_by(time, x)` returns the timestamp when x reaches its minimum value.
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- Returns null if x is null at the timestamp where y is minimum.
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- If y achieves its minimum at multiple timestamps, returns the x value at the smallest timestamp among them.
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- Aligns with IoTDB's `min_value`: Only supports INT32, INT64, FLOAT, DOUBLE as y input. Supports all six data types as x input.
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- Inputs x and y cannot be literal values.
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#### Syntax
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```sql
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select min_by(x, y) from root.sg
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select min_by(time, x) from root.sg
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```
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#### Examples
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##### Raw Data
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```sql
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IoTDB> select * from root.test
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+-----------------------------+-----------+-----------+
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| Time|root.test.a|root.test.b|
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+-----------------------------+-----------+-----------+
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|1970-01-01T08:00:00.001+08:00| 4.0| 10.0|
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|1970-01-01T08:00:00.002+08:00| 3.0| 10.0|
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|1970-01-01T08:00:00.003+08:00| 2.0| 3.0|
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|1970-01-01T08:00:00.004+08:00| 1.0| 10.0|
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|1970-01-01T08:00:00.005+08:00| 1.0| 12.0|
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|1970-01-01T08:00:00.006+08:00| 6.0| 6.0|
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+-----------------------------+-----------+-----------+
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```
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##### Query Examples
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Get timestamp corresponding to minimum value:
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```sql
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IoTDB> select min_by(time, a), min_value(a) from root.test
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+-------------------------+------------------------+
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|min_by(Time, root.test.a)| min_value(root.test.a)|
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+-------------------------+------------------------+
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| 4| 1.0|
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+-------------------------+------------------------+
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```
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Get b value when a is minimum:
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```sql
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IoTDB> select min_by(b, a) from root.test
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+--------------------------------+
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|min_by(root.test.b, root.test.a)|
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+--------------------------------+
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| 10.0|
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+--------------------------------+
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```
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With expressions:
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```sql
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IoTDB> select min_by(b + 1, a * 2) from root.test
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+----------------------------------------+
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|min_by(root.test.b + 1, root.test.a * 2)|
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+----------------------------------------+
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| 11.0|
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+----------------------------------------+
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```
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With GROUP BY TIME clause:
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```sql
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IoTDB> select min_by(b, a) from root.test group by ([0,7),4ms)
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+-----------------------------+--------------------------------+
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| Time|min_by(root.test.b, root.test.a)|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.000+08:00| 3.0|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.004+08:00| 10.0|
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+-----------------------------+--------------------------------+
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```
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With HAVING clause:
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```sql
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IoTDB> select min_by(b, a) from root.test group by ([0,7),4ms) having max_by(b, a) > 4.0
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+-----------------------------+--------------------------------+
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| Time|min_by(root.test.b, root.test.a)|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.004+08:00| 10.0|
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+-----------------------------+--------------------------------+
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```
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With ORDER BY clause:
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```sql
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IoTDB> select min_by(b, a) from root.test group by ([0,7),4ms) order by time desc
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+-----------------------------+--------------------------------+
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| Time|min_by(root.test.b, root.test.a)|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.004+08:00| 10.0|
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+-----------------------------+--------------------------------+
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|1970-01-01T08:00:00.000+08:00| 3.0|
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+-----------------------------+--------------------------------+
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```
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