# Type conversion functions
<a name="sql-functions-type-conv"></a>

 Type conversion functions are used to change the data type of a value from one to another. They are essential for ensuring data compatibility and performing operations that require data in a specific format. 


|  **Function**  |  **Signature**  |  **Description**  | 
| --- | --- | --- | 
|  `TO_DATE`  |  [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/iot-sitewise/latest/userguide/sql-functions-type-conv.html)  |  [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/iot-sitewise/latest/userguide/sql-functions-type-conv.html)  | 
|  `TO_TIMESTAMP`  |  [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/iot-sitewise/latest/userguide/sql-functions-type-conv.html)  |  [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/iot-sitewise/latest/userguide/sql-functions-type-conv.html)  | 
|  `TO_TIME`  |  [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/iot-sitewise/latest/userguide/sql-functions-type-conv.html)  |  [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/iot-sitewise/latest/userguide/sql-functions-type-conv.html)  | 
|  `CAST`  |  CAST (<expression> AS <data type>)  |  Converts an entity, or expression that evaluates to a single value, from one type to another. Supported data types are: [\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/iot-sitewise/latest/userguide/sql-functions-type-conv.html)  | 

**Example of a SQL query using the listed functions:**  

```
SELECT TO_TIMESTAMP (100) AS timestamp_value,
  TO_DATE(r.event_timestamp) AS date_value,
  TO_TIME(r.event_timestamp) AS time_value
FROM raw_time_series AS r
```