---
parser: v2
time: 20
author_name: Thomas Jung
author_profile: https://github.com/jung-thomas
tags: [ tutorial>beginner, products>sap-hana, products>sap-hana-cloud, products>sap-business-application-studio]
primary_tag: products>sap-hana
slug: hana-cloud-calculation-view-differential-privacy
canonical_url: https://developers.sap.com/tutorials/hana-cloud-calculation-view-differential-privacy
---

# Create a Calculation View with Differential Privacy in SAP HANA Cloud
<!-- description --> Use differential privacy to anonymize confidential data in SAP HANA Cloud.

## Prerequisites

- You have completed the previous tutorials in this series specially [Create an SAP HANA Database Project](hana-cloud-create-db-project)

## You will learn

- How to create Calculation View of type Cube using SAP Business Application Studio
- How to configure data anonymization to a column in order to protect sensitive data

## Intro

A video version of this tutorial is also available:

<iframe width="560" height="315" src="https://www.youtube.com/embed/kZhATB7yJ-M" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

---

### Create a salary table and load data into it

Using what you learned in [Create an SAP HANA Database Project](hana-cloud-create-db-project), you will create another database table and load sample data into it but without step by step instructions. Extrapolate what you learned from these same steps in the earlier tutorial to complete this task.

1. Create a new database table named `TGT_SALARIES` using the `hdbtable` artifact type in the data folder. Use the following table definition.

   ```SQL
   column table "TGT_SALARIES" (
	    ID INTEGER  unique not null COMMENT 'Employee ID',
	    SALARY DOUBLE COMMENT 'Salary',
	    START_YEAR INTEGER not null COMMENT 'Starting Year',
	    GENDER NVARCHAR(1) COMMENT 'Gender',
       REGION NVARCHAR(4) COMMENT 'Region',
       "T-LEVEL" NVARCHAR(200) COMMENT 'T Level',
	    PRIMARY KEY ("ID")
   )
   COMMENT 'Employee Salary'
   ```

2. Create the configuration for the `csv` upload.  In the `data/loads` folder, create a file called `salaryload.hdbtabledata` with the following content

   ```json
   {
     "format_version": 1,
     "imports": [{
       "target_table": "TGT_SALARIES",
       "source_data": {
         "data_type": "CSV",
         "file_name": "salarydata.csv",
         "has_header": true,
         "dialect": "HANA",
         "type_config": {
           "delimiter": ","
         }
       }
       }]
   }		
   ```

3. Download this `csv` file -- `https://github.com/SAPDocuments/Tutorials/blob/master/tutorials/hana-cloud-calculation-view-differential-privacy/salarydata.csv` into your computer. Upload it into the **loads** folder using the **Upload Files** option.

4. **Deploy** these new Artifacts

    ![Salary Table](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/intro.png)

### Create a new calculation view

1. Create a new folder called **models** under `db/src`. Create a new **Calculation View** via the **SAP HANA: Create SAP HANA Database Artifact** command pallet entry.

    ![New calculation view](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/1_0.png)

2. Call it `SALARIES_ANONYMIZED` and make it a **CUBE**. Press **Create**.

    ![New calculation view](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/1.png)

3. Select the new calculation view file in the **Explorer**. This will load it into the graphical Calculation View editor. Click on the `Projection` node and then click on the white canvas to drop it.

    ![New calculation view](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/2.png)

4. Use the ![plus sign](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/3.png) on the node to add a table as a data source. Choose `TGT_SALARIES`

    ![New calculation view](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/4.png)

### Complete the calculation View

1. Double click on the `Projection_1` node. This will open the mapping. Double click on `TGT_SALARIES` to add all of the columns to the output

    ![New calculation view](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/5.png)

2. Connect the `Projection_1` node to the **Aggregation** node.

    ![Configure privacy](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/1.gif)

3. Double-click on the name of the node to move all the fields into the output columns.

    ![Configure privacy](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/8.png)

4. Go into the **Semantics** node and switch `START_YEAR` and `ID` to attribute

    ![Configure privacy](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/12.png)

5. **Deploy**

### Configure differential privacy via SQL view

1.  Create a view (artifact type `hdbview`) in the `src/models` folder named `V_SALARIES`.

    ![Configure privacy](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/6.png)

2. Use the following syntax to create a SQL view that uses the **Differential Privacy** Anonymization approach for the **SALARY** column.

   ```SQL
   VIEW V_SALARIES (
     ID,
     SALARY,
     START_YEAR,
     GENDER,
     REGION,
     "T-LEVEL"
   ) AS
   SELECT ID,
     SALARY,
     START_YEAR,
     GENDER,
     REGION,
     "T-LEVEL"
   FROM "SALARIES_ANONYMIZED"
   WITH READ ONLY
   WITH ANONYMIZATION (ALGORITHM 'DIFFERENTIAL_PRIVACY'
     PARAMETERS '{"data_change_strategy": "qualified"}'
     COLUMN ID PARAMETERS '{"is_sequence": true}'
     COLUMN SALARY PARAMETERS '{"is_sensitive":true, "epsilon":0.1, "sensitivity":15000}')
   ```

    > For more information about these parameters check the [SAP HANA Cloud Data Anonymization Guide](https://help.sap.com/viewer/2f789e82e97d4f4e9416547abfbd012e/latest/en-US/a66e8541c4004f048630f8a55f67ad37.html)

3. If you receive an error that the feature is not supported, this can be safely ignored.

    ![Configure privacy](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/7.png)

4. **Deploy**

### Preview data

1. Open the Database Explorer for your project

    ![Data Preview](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/13.png)

2. Open a SQL Console and issue the following statement   

   ```SQL
   refresh view V_SALARIES anonymization;
   ```

3.  Execute that statement in the SQL console

    ![Data Preview](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/14.png)

4.  You can now use the normal **Open Data** on the view to preview the Raw Data.

    ![Data Preview](https://raw.githubusercontent.com/sap-tutorials/Tutorials/master/tutorials/hana-cloud-calculation-view-differential-privacy/15.png)


---