# Understanding security boundaries with structured data sources in an Amazon Bedrock knowledge base
Security boundaries in structured data sources

Use the following information to understand how security boundaries affect structured data sources in an Amazon Bedrock knowledge base.

**Topics**
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## Accessing structured data in an Amazon Bedrock knowledge base
](#kb-data-access)
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## Database and table selection as query guidelines
](#kb-query-guidelines)
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## Reliable security boundaries
](#kb-reliable-boundaries)
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## Best practices for sensitive data
](#kb-best-practices)

## Accessing structured data in an Amazon Bedrock knowledge base


When you create an Amazon Bedrock knowledge base with a structured data source such as Amazon Redshift, the knowledge base operates with the same permissions as your project user role. This means the knowledge base can potentially access any data that your project role has permission to access. This includes all databases accessible to your project and tables within those databases (both owned by your project and subscribed from other projects through the Business Data Catalog).

## Database and table selection as query guidelines


Configure your knowledge base by selecting a database and specifying which tables and columns to use. Customize your selection by including or excluding tables and columns according to your requirements. These selections help the knowledge base generate more accurate SQL queries by:
+ Focusing the model on relevant data sources
+ Reducing unnecessary references to irrelevant tables or columns
+ Helping prioritize which data should be considered when answering queries

However, due to the nature of large language model based SQL generation:
+ These selections are treated as recommendations rather than strict security boundaries.
+ The knowledge base may occasionally generate queries that reference databases, tables, or columns outside your specified selections.
+ Actual query execution is still governed by your project's permissions.

## Reliable security boundaries


The guaranteed security boundary is at the project level. A knowledge base can never access data from another project unless that data has been explicitly shared with your project. All data access is subject to authentication and authorization through AWS Identity and Access Management and Amazon DataZone project permissions.

## Best practices for sensitive data


If your project contains both sensitive and non-sensitive data, and you want to ensure the knowledge base only accesses specific non-sensitive data, consider these approaches:

### Create a Dedicated *knowledge base-safe* project

+ Create a separate project specifically for knowledge base usage
+ Use the Business Data Catalog to publish only non-sensitive tables from source projects
+ Have your knowledge base-safe project subscribe only to the tables intended for knowledge base access
+ Build knowledge bases exclusively in this controlled environment

### Implement guardrails in your chat agent app

+ Deploy guardrails to detect and block prompts that attempt to manipulate the knowledge base.
+ Configure content filtering to prevent SQL injection patterns in prompts.
+ Set up rejection criteria for prompts that try to bypass configured constraints.

For information about guardrails, see [Safeguard your Amazon Bedrock app with a guardrail](guardrails.md).