# Structural differences and limitations with DynamoDB

Amazon DynamoDB is a document-based database.

For workspaces that use DynamoDB, the Tonic Structural application has the following differences.

## Terminology changes <a href="#terminology" id="terminology"></a>

On the following Structural views, the term "collection" replaces the term "table":

* **Privacy Hub**
* **Schema Changes**

References to columns are also replaced:

* On **Privacy Hub**, the protection status panels refer to "fields" instead of "columns".
* On the **Schema Changes** view, the change lists refer to "paths" instead of "columns".

## No schema caching

Amazon DynamoDB does not allow you to cache the database schema.

## Privacy Hub - Latest Collection Scan <a href="#privacy-hub-collection-scan" id="privacy-hub-collection-scan"></a>

For DynamoDB workspaces, Structural must scan each collection to determine the fields and data types within that collection. Until a scan is performed, you cannot configure the collection modes and generators.

For DynamoDB workspaces, Privacy Hub includes an additional Latest Collection Scan section that shows the most recent time that a scan was performed on each scanned collection.

For more information, go to [mongodb-collection-scans](https://docs.tonic.ai/app/generation/working-with-document-based-data/mongodb-collection-scans "mention").

## No Privacy Report downloads

For DynamoDB workspaces, there are no options to download a Privacy Report CSV or PDF.

## No workspace inheritance

DynamoDB workspaces do not support workspace inheritance.

## Collection View replaces Database View and Table View <a href="#dynamodb-collection-view" id="dynamodb-collection-view"></a>

For DynamoDB workspaces, there is no **Database View** or **Table View**. Instead, DynamoDB workspaces have a **Collection View**.

This view allows you to perform the same functions as **Table View**, but the display is more like **Database View**. For more information, go to [mongodb-collection-view](https://docs.tonic.ai/app/generation/working-with-document-based-data/mongodb-collection-view "mention").

## Collection mode (table mode) limitations <a href="#dynamodb-collection-mode" id="dynamodb-collection-mode"></a>

Collection mode is the term for table mode in DynamoDB workspaces.

DynamoDB only supports De-Identify, Truncate, and Preserve Destination modes.

## Generator limitations <a href="#dynamodb-generator-support" id="dynamodb-generator-support"></a>

DynamoDB workspaces cannot use the following generators:

* Algebraic
* Alphanumeric Key
* Array Character Scramble
* Array JSON Mask
* Array Regex Mask
* Cross-Table Sum
* CSV Mask
* Event Timestamps
* HTML Mask
* JSON Mask
* SIN
* Text Composition
* URL

## Self-consistency only <a href="#dynamodb-self-consistency-only" id="dynamodb-self-consistency-only"></a>

DynamoDB workspaces only support self-consistency.

You cannot make a DynamoDB field consistent with another field.

## No subsetting

DynamoDB workspaces do not support subsetting.

## No upsert

DynamoDB workspaces do not support upsert.

## No output to a container repository <a href="#no-output-to-repo" id="no-output-to-repo"></a>

For DynamoDB workspaces, you cannot write the destination data to a container repository.

## No post-job scripts

For DynamoDB workspaces, there is no option to run post-job scripts after a job.

You can create webhooks that are triggered by data generation jobs.