Lakehouse Cross-instance Data Sharing Guide (Share)

Overview

Cross-instance Data Sharing allows you to securely share tables or views from your Lakehouse with users in other instances without copying data. Through CREATE SHARE and GRANT commands, you can finely control the sharing scope and permissions. This guide is organized by business scenario to help you quickly master data sharing configuration methods.

Quick Navigation

• Create Data Share -- Define a share object
• Grant Tables to Share -- Add tables to a share
• Add Consumer Instance -- Specify target instances that can access the share
• View Share Information -- Monitor share status
• Revoke Share -- Remove share permissions or delete the share

SQL Commands Covered

Prerequisites

The following examples use a simulated shared table shared_sales:

-- Create test table
CREATE TABLE IF NOT EXISTS shared_sales (
    sale_id INT,
    product STRING,
    amount DOUBLE,
    sale_date DATE
);

-- Insert test data
INSERT INTO shared_sales VALUES
(1, 'Phone', 5000, '2024-06-01'),
(2, 'Laptop', 8000, '2024-06-02');

Create Data Share

Use CREATE SHARE to define a share object, which serves as the container for data sharing.

-- Create a share
CREATE SHARE sales_share;

Grant Tables to Share

Use the GRANT command to grant read permissions on tables or views to a share object.

-- Grant table read permission to the share
GRANT SELECT ON TABLE shared_sales TO SHARE sales_share;

Supported Permissions:

• SELECT: Allows the consumer instance to query table data.
• READ METADATA: Allows the consumer instance to view table structure (schema).

Add Consumer Instance

Use ALTER SHARE to add a target Lakehouse instance to the share, enabling it to access shared data.

-- Add a consumer instance (replace with the actual instance ID)
ALTER SHARE sales_share ADD INSTANCE 'consumer_instance_id';

View Share Information

Use SHOW SHARES to view all share configurations for the current instance.

-- View share list
SHOW SHARES;

-- View share details
DESC SHARE sales_share;

Returned Information:

• share_name: Share name
• kind: Share type (OUTBOUND / INBOUND)
• objects: List of shared tables/views

Revoke Share

Use REVOKE or DROP SHARE to remove share permissions.

-- Revoke table share permission
REVOKE SELECT ON TABLE shared_sales FROM SHARE sales_share;

-- Drop the share
DROP SHARE sales_share;

Clean Up Test Data

After completing share verification, it is recommended to clean up test data:

-- Drop test table
DROP TABLE IF EXISTS shared_sales;
DROP SHARE IF EXISTS sales_share;

Notes

1. Read-only Sharing: Shares only support SELECT permissions; consumer instances cannot modify source table data.
2. Real-time: When a consumer instance queries shared tables, it reads the latest data from the source instance with no synchronization delay.
3. Network Policies: Cross-cloud or cross-region sharing requires network policies (such as PrivateLink) to be correctly configured.
4. Permission Inheritance: Row-level permissions or dynamic masking policies on shared tables are synchronously applied to consumer instances.
5. Billing: Compute resource costs from share queries are borne by the consumer instance; storage costs are borne by the provider.

Related Documentation

• Data Sharing
• CREATE SHARE
• GRANT TO SHARE