Implementing Row-Level Security in Microsoft Fabric for Multi-Ward Healthcare Dashboards

Implementing Row-Level Security in Microsoft Fabric for Multi-Ward Healthcare Dashboards

Understanding Row-Level Security in Healthcare Data Environments

Row-level security (RLS) is a critical capability for healthcare organisations managing sensitive patient data across multiple wards, departments, and clinical teams. In Australia, where privacy compliance under the Australian Privacy Principles and Health Records Act is mandatory, implementing robust data access controls is not optional but essential. Microsoft Fabric provides enterprise-grade row-level security mechanisms that enable healthcare providers to restrict data visibility based on user roles, ward assignments, and clinical responsibilities.

When healthcare dashboards span multiple wards, different clinicians need access to different subsets of patient data. A nurse on the cardiac ward should not see psychiatric patient records, and financial administrators should only view billing data relevant to their cost centres. Without proper row-level security, you risk exposing sensitive health information and creating compliance violations. Microsoft Fabric’s RLS capabilities allow you to enforce these restrictions at the data warehouse level, ensuring that security is applied consistently across all downstream reports and dashboards.

The power of Fabric’s approach lies in its ability to apply security policies at the source, meaning restrictions are enforced whether users access data through Power BI dashboards, SQL endpoints, or direct queries. This centralised security model simplifies governance and reduces the risk of accidental data exposure through alternative access paths.

Prerequisites and Environment Setup

Before implementing row-level security in your Fabric environment, you need to ensure several foundational elements are in place. First, you must have a Microsoft Fabric tenant provisioned with appropriate capacity. For healthcare organisations, we recommend a dedicated Fabric capacity to ensure performance isolation and compliance with data residency requirements. Your organisation should also have Azure Entra ID (formerly Azure AD) configured with security groups representing your ward structures and clinical roles.

You’ll need administrative access to your Fabric workspace and the underlying Fabric Data Warehouse or Lakehouse where you plan to implement RLS. Your healthcare data should already be ingested into Fabric through appropriate connectors, whether from your Electronic Health Record (EHR) system, hospital information system, or data lake. If you’re migrating from legacy analytics platforms, reviewing our guide on Migrating to Microsoft Fabric for Government Agencies can provide valuable context on governance considerations during transition.

Install the latest version of SQL Server Management Studio (SSMS) or use the Fabric Data Warehouse query editor for direct policy creation. Ensure you have a test environment separate from production where you can validate RLS policies before deployment. This staging environment should mirror your production data structure but contain anonymised or synthetic patient data for testing purposes.

Your team should have basic understanding of DAX (Data Analysis Expressions) for Power BI integration, though Fabric Data Warehouse RLS uses T-SQL security predicates. If your organisation is planning broader Microsoft Fabric adoption, exploring the Microsoft Fabric 2026 Update: New Features Enterprises Need to Know will help you understand emerging capabilities that complement RLS implementation.

Document your current user access patterns and ward structures in a spreadsheet or governance tool. This mapping will become your RLS policy blueprint. For example, you might map users to wards like: Cardiac Ward (users: Dr Smith, Nurse Johnson), Psychiatric Ward (users: Dr Williams, Nurse Brown), and so on. This clear mapping prevents policy gaps and ensures no users accidentally gain inappropriate access.

Creating Your Healthcare Data Structure in Fabric Data Warehouse

The foundation of effective row-level security is a well-designed data model. In Fabric Data Warehouse, you’ll typically have a fact table containing patient encounters, treatments, or clinical observations, and dimension tables for patients, wards, staff, and dates. For healthcare dashboards spanning multiple wards, your patient dimension should include a ward assignment attribute, and your encounters or treatments fact table should reference this dimension.

Start by creating a simple schema in your Fabric Data Warehouse. Your primary fact table might be named PatientEncounters, containing encounter IDs, patient IDs, ward IDs, admission dates, discharge dates, diagnosis codes, and treatment details. The PatientDimension table should include PatientID, PatientName, WardID, AdmissionWard, and CurrentWard fields. Create a WardDimension table with WardID, WardName, and DepartmentID. Additionally, create a UserWardMapping table that links Azure Entra ID user identities to their authorised wards.

This UserWardMapping table is crucial for RLS implementation. It should contain UserPrincipalName (the Azure Entra ID email address), WardID, and AccessLevel (for example, ‘View’, ‘Edit’, ‘Admin’). By maintaining this mapping in a database table rather than hardcoding it into policies, you enable dynamic updates without modifying security predicates. When staff rotate between wards, you simply update this mapping table.

Here’s a sample T-SQL script to create these foundational tables in your Fabric Data Warehouse:

CREATE TABLE WardDimension (
    WardID INT PRIMARY KEY,
    WardName NVARCHAR(100) NOT NULL,
    DepartmentID INT NOT NULL,
    DepartmentName NVARCHAR(100) NOT NULL
);

CREATE TABLE UserWardMapping (
    UserID INT PRIMARY KEY IDENTITY(1,1),
    UserPrincipalName NVARCHAR(255) NOT NULL UNIQUE,
    WardID INT NOT NULL,
    AccessLevel NVARCHAR(50) NOT NULL,
    FOREIGN KEY (WardID) REFERENCES WardDimension(WardID)
);

CREATE TABLE PatientDimension (
    PatientID INT PRIMARY KEY,
    PatientName NVARCHAR(255) NOT NULL,
    DateOfBirth DATE NOT NULL,
    CurrentWardID INT NOT NULL,
    FOREIGN KEY (CurrentWardID) REFERENCES WardDimension(WardID)
);

CREATE TABLE PatientEncounters (
    EncounterID INT PRIMARY KEY IDENTITY(1,1),
    PatientID INT NOT NULL,
    WardID INT NOT NULL,
    AdmissionDate DATETIME NOT NULL,
    DischargeDate DATETIME NULL,
    DiagnosisCode NVARCHAR(50) NOT NULL,
    TreatmentDescription NVARCHAR(MAX),
    FOREIGN KEY (PatientID) REFERENCES PatientDimension(PatientID),
    FOREIGN KEY (WardID) REFERENCES WardDimension(WardID)
);

Once these tables are created, populate them with your healthcare data. The UserWardMapping table should be maintained by your IT or data governance team and updated whenever staff assignments change. This separation of concerns ensures that RLS policies remain stable while access mappings evolve with your organisation.

Implementing Security Predicates in Fabric Data Warehouse

Row-level security in Fabric Data Warehouse is implemented using security predicates, which are T-SQL functions that filter data based on the current user’s context. Following the official guidance on Implement Row-Level Security in Fabric Data Warehouse, you’ll create inline table-valued functions (ITVFs) that define access rules.

First, create a security predicate function that filters the PatientEncounters table based on the current user’s ward assignments. This function will be invoked automatically whenever someone queries the table, ensuring consistent enforcement:

CREATE FUNCTION dbo.fn_securitypredicate(@WardID INT)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN
    SELECT 1 AS fn_securitypredicate_result
    WHERE @WardID IN (
        SELECT WardID
        FROM dbo.UserWardMapping
        WHERE UserPrincipalName = CAST(SESSION_CONTEXT(N'UserPrincipalName') AS NVARCHAR(255))
    )
    OR CAST(SESSION_CONTEXT(N'UserRole') AS NVARCHAR(50)) = 'Administrator';

This function checks if the current user’s principal name (stored in session context) has access to the specified ward. It also includes an administrator bypass, allowing system administrators full data access for troubleshooting and governance purposes. The SCHEMABINDING clause ensures the function is tied to the underlying tables, improving performance.

Next, create a security policy that applies this predicate to your PatientEncounters table:

CREATE SECURITY POLICY dbo.PatientEncountersSecurity
ADD FILTER PREDICATE dbo.fn_securitypredicate(WardID)
ON dbo.PatientEncounters
WITH (STATE = ON);

Before testing, you need to populate the SESSION_CONTEXT with the current user’s information. This is typically done through your application layer or through a stored procedure that users execute at the start of their session. Create a setup procedure:

CREATE PROCEDURE dbo.sp_SetUserContext
AS
BEGIN
    DECLARE @UserPrincipalName NVARCHAR(255) = CAST(SESSION_USER AS NVARCHAR(255));
    DECLARE @UserRole NVARCHAR(50);

    SELECT @UserRole = AccessLevel
    FROM dbo.UserWardMapping
    WHERE UserPrincipalName = @UserPrincipalName;

    EXEC sp_set_session_context @key = N'UserPrincipalName', @value = @UserPrincipalName;
    EXEC sp_set_session_context @key = N'UserRole', @value = @UserRole;
END;

For more detailed implementation steps, the comprehensive guide on Row Level Security In Microsoft Fabric provides additional context on service principal configurations and policy management.

Testing Row-Level Security Policies

Testing is critical before deploying RLS to production. In your test environment, create test users representing different ward roles and verify that each user sees only appropriate data. Start by inserting test data into your tables:

INSERT INTO WardDimension VALUES
(1, 'Cardiac Ward', 1, 'Cardiology'),
(2, 'Psychiatric Ward', 2, 'Mental Health'),
(3, 'Orthopedic Ward', 1, 'Orthopedics');

INSERT INTO UserWardMapping VALUES
('cardiacnurse@hospital.onmicrosoft.com', 1, 'View'),
('psychiatrist@hospital.onmicrosoft.com', 2, 'View'),
('administrator@hospital.onmicrosoft.com', 1, 'Administrator');

INSERT INTO PatientDimension VALUES
(1, 'John Smith', '1965-03-15', 1),
(2, 'Jane Doe', '1978-07-22', 2),
(3, 'Robert Johnson', '1952-11-08', 3);

INSERT INTO PatientEncounters VALUES
(1, 1, '2024-01-10', '2024-01-15', 'I50.9', 'Heart failure management'),
(2, 2, '2024-01-12', NULL, 'F32.9', 'Depression treatment'),
(3, 3, '2024-01-14', '2024-01-20', 'M17.11', 'Knee replacement surgery');

Now, test the security by executing queries as different users. Simulate the cardiac nurse’s session:

EXEC dbo.sp_SetUserContext;

SELECT *
FROM dbo.PatientEncounters;

When executed as the cardiac nurse (cardiacnurse@hospital.onmicrosoft.com), this query should return only the encounter for WardID 1 (Cardiac Ward). The psychiatric patient record should be invisible. Execute the same query as the psychiatrist user, and you should see only the psychiatric ward encounter.

For comprehensive testing guidance, review the YouTube tutorial on Row-level security in Fabric Warehouse & SQL Endpoint, which demonstrates group-based access control and departmental data restrictions in action.

Test edge cases: What happens when a user is assigned to multiple wards? Your security predicate should return data for all their assigned wards. Test administrator access: administrators should see all patient encounters regardless of ward assignment. Test what happens when a user has no ward assignments: they should see no data.

Create a test report in Power BI that queries the PatientEncounters table and verify that RLS filters are applied correctly. When different users view the same dashboard, they should see different data based on their ward assignments. This end-to-end testing ensures that RLS works not just at the warehouse level but through the entire analytics stack.

Connecting Power BI Dashboards with Row-Level Security

Once your Fabric Data Warehouse RLS is configured and tested, connecting Power BI dashboards is straightforward. Your Power BI reports can directly query the secured tables, and Fabric automatically applies the row-level security based on the user’s identity. This means your multi-ward healthcare dashboard automatically shows different data to different users without requiring separate reports or manual filtering.

In Power BI Desktop, create a new data source connecting to your Fabric Data Warehouse. Use the SQL Server connector and point to your Fabric warehouse endpoint. When you query the PatientEncounters table, Power BI will use your user’s Azure Entra ID credentials, and Fabric will apply the security predicate automatically.

Create your dashboard visualisations as normal: patient census by ward, admission trends, treatment outcomes, and so on. The key difference is that when you publish this report to the Power BI service and different users view it, each user sees only the data they’re authorised to access. A cardiac ward nurse viewing the patient census chart sees only cardiac patients. A psychiatric clinician sees only psychiatric patients.

For optimal performance with RLS, use aggregated tables or materialised views in your Fabric Data Warehouse. Instead of applying RLS to raw fact tables with millions of rows, create pre-aggregated tables (for example, DailyWardCensus, MonthlyAdmissions) and apply RLS to these. This reduces the computational overhead of filtering at query time. The Power BI blog announcement on Row-level security provides healthcare-relevant multi-tenant examples showing this approach.

Ensure that your Power BI reports use Direct Query or Import mode appropriately. With Direct Query, every user interaction queries the secured Fabric warehouse, ensuring real-time security. With Import mode, ensure you refresh data frequently and that row-level security in Power BI is configured to match your Fabric warehouse policies.

Managing Dynamic Ward Assignments and Role Changes

Healthcare organisations experience frequent staff changes, ward rotations, and role transitions. Your RLS implementation must accommodate these changes without requiring security policy modifications. This is why the UserWardMapping table approach is superior to hardcoding ward assignments into security predicates.

When a nurse rotates from the cardiac ward to the psychiatric ward, you simply update the UserWardMapping table:

UPDATE dbo.UserWardMapping
SET WardID = 2
WHERE UserPrincipalName = 'cardiacnurse@hospital.onmicrosoft.com';

The next time this user accesses a dashboard or runs a query, they automatically see psychiatric ward data instead of cardiac ward data. No security policy modification is required.

For temporary access (for example, a specialist covering another ward for a shift), insert a new row:

INSERT INTO UserWardMapping VALUES
('cardiacnurse@hospital.onmicrosoft.com', 2, 'View');

This allows the user to access both wards. After the shift, delete the temporary mapping. For more complex scenarios involving multiple roles and access levels, consider extending your UserWardMapping table with effective date and expiration date columns:

ALTER TABLE dbo.UserWardMapping
ADD EffectiveDate DATETIME DEFAULT GETDATE(),
ExpirationDate DATETIME NULL;

ALTER FUNCTION dbo.fn_securitypredicate(@WardID INT)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN
    SELECT 1 AS fn_securitypredicate_result
    WHERE @WardID IN (
        SELECT WardID
        FROM dbo.UserWardMapping
        WHERE UserPrincipalName = CAST(SESSION_CONTEXT(N'UserPrincipalName') AS NVARCHAR(255))
        AND EffectiveDate <= GETDATE()
        AND (ExpirationDate IS NULL OR ExpirationDate >= GETDATE())
    )
    OR CAST(SESSION_CONTEXT(N'UserRole') AS NVARCHAR(50)) = 'Administrator';

This time-based approach allows you to schedule access changes in advance. A staff member’s access automatically expires at a specified date without manual intervention. This is particularly valuable for maternity leave coverage, sabbaticals, or planned role transitions.

Implementing RLS in Fabric Lakehouse Environments

While Fabric Data Warehouse is the primary RLS-enabled storage option, many healthcare organisations also use Fabric Lakehouse for data lake scenarios. The guide on Fabric Lakehouse row-level security implementation outlines how to secure Lakehouse data through SQL endpoints.

Fabric Lakehouse provides a SQL endpoint that functions like a data warehouse, allowing you to apply RLS policies to lakehouse tables. Create your security predicates and policies on the lakehouse SQL endpoint using the same T-SQL approach described earlier. The advantage is that you can maintain both structured data warehouse tables and semi-structured lakehouse data under unified RLS governance.

If you’re using Lakehouse for raw data ingestion and Fabric Data Warehouse for curated analytics, implement RLS at both layers. Apply restrictive RLS in the Lakehouse SQL endpoint to prevent accidental exposure during data exploration, and apply more granular RLS in the Data Warehouse for specific analytics use cases.

For organisations evaluating whether Fabric Data Warehouse or Lakehouse better suits their architecture, the comparison guide Microsoft Fabric vs Azure Synapse: Which Is Best for Your Data Platform? provides architectural context on storage options and security capabilities.

Monitoring, Auditing, and Compliance

Implementing RLS is only the first step. Ongoing monitoring and auditing ensure that security policies remain effective and that no unauthorised access occurs. Enable Fabric audit logs to track who accesses what data. In the Fabric admin portal, configure audit logging to capture all queries against your secured tables.

Create a dashboard that monitors RLS policy violations and suspicious access patterns. For example, alert if an administrator accesses psychiatric ward data (which might be legitimate but warrants review), or if a user queries wards they’re not assigned to (which should be blocked by RLS but indicates a potential configuration issue).

Regularly audit your UserWardMapping table to ensure it accurately reflects current staff assignments. Implement a quarterly review process where ward managers confirm that their team members’ access mappings are correct. This prevents access creep (where users retain access to previous wards after transferring) and ensures compliance with the principle of least privilege.

For healthcare organisations subject to Australian Privacy Principles, document your RLS implementation as part of your data governance framework. Create a data access policy document that explains how row-level security protects patient privacy. This documentation is valuable for privacy impact assessments and demonstrates due diligence in protecting sensitive health information.

Test RLS effectiveness through penetration testing. Engage your security team to attempt accessing data they shouldn’t see. If they succeed, you’ve identified a gap in your implementation. If they cannot access unauthorised data despite having database access, your RLS is functioning correctly.

Troubleshooting Common RLS Implementation Issues

Even with careful implementation, RLS issues can arise. Here are common problems and solutions:

Issue: Users see no data even though they should have access. Check that their UserPrincipalName in the UserWardMapping table exactly matches their Azure Entra ID email address, including case sensitivity. Verify that the SESSION_CONTEXT is being set correctly by executing the sp_SetUserContext procedure. Confirm that the user’s ward ID exists in the WardDimension table and that the foreign key relationship is intact.

Issue: Administrators cannot see all data. Ensure that your security predicate includes the administrator bypass clause and that the user’s AccessLevel in UserWardMapping is set to ‘Administrator’. Verify that SESSION_CONTEXT(‘UserRole’) is being set to ‘Administrator’ when they execute sp_SetUserContext.

Issue: Performance degrades after implementing RLS. This often occurs when RLS predicates are applied to large fact tables. Solution: Create indexed views or materialised tables at the appropriate aggregation level and apply RLS to these instead of raw fact tables. Use execution plans to identify slow queries and add appropriate indexes on the columns used in security predicates.

Issue: RLS works in Power BI but not in SSMS or SQL clients. Different tools may handle SESSION_CONTEXT differently. Always execute sp_SetUserContext as part of your connection setup. Consider creating a login trigger that automatically sets SESSION_CONTEXT for all connections.

Issue: New users cannot access data. Ensure they have been added to the UserWardMapping table and that their ward ID is valid. Check that they have appropriate permissions on the underlying tables (SELECT permission is sufficient for read-only access). Verify that they are not blocked by other database-level security policies.

For SQL Server-specific RLS troubleshooting that applies to Fabric Data Warehouse, the comprehensive tutorial on Implementing Row-Level Security in SQL Server provides detailed diagnostic approaches.

Advanced Scenarios: Multi-Level Hierarchies and Conditional Access

Simple ward-based RLS works for many healthcare scenarios, but some organisations require more sophisticated access patterns. Consider a health system with multiple hospitals, each with multiple wards. A clinician might have access to all wards in their home hospital but only specific wards in partner hospitals.

Extend your UserWardMapping table to include hospital information:

ALTER TABLE dbo.UserWardMapping
ADD HospitalID INT,
FOREIGN KEY (HospitalID) REFERENCES HospitalDimension(HospitalID);

Modify your security predicate to check both hospital and ward:

ALTER FUNCTION dbo.fn_securitypredicate(@HospitalID INT, @WardID INT)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN
    SELECT 1 AS fn_securitypredicate_result
    WHERE (@HospitalID, @WardID) IN (
        SELECT HospitalID, WardID
        FROM dbo.UserWardMapping
        WHERE UserPrincipalName = CAST(SESSION_CONTEXT(N'UserPrincipalName') AS NVARCHAR(255))
    )
    OR CAST(SESSION_CONTEXT(N'UserRole') AS NVARCHAR(50)) = 'Administrator';

For conditional access based on patient sensitivity (for example, VIP patients, research subjects), create an additional security predicate:

CREATE FUNCTION dbo.fn_patientSensitivityPredicate(@PatientSensitivity NVARCHAR(50))
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN
    SELECT 1 AS fn_patientSensitivityPredicate_result
    WHERE @PatientSensitivity IN (
        SELECT AllowedSensitivityLevel
        FROM dbo.UserAccessLevels
        WHERE UserPrincipalName = CAST(SESSION_CONTEXT(N'UserPrincipalName') AS NVARCHAR(255))
    );

CREATE SECURITY POLICY dbo.PatientSensitivitySecurity
ADD FILTER PREDICATE dbo.fn_patientSensitivityPredicate(PatientSensitivityLevel)
ON dbo.PatientEncounters
WITH (STATE = ON);

This layered approach ensures that even if a user has access to a ward, they cannot see highly sensitive patient records unless explicitly authorised.

Integration with Azure OpenAI and Governance

As healthcare organisations increasingly adopt AI-powered analytics, integrating RLS with Azure OpenAI and Copilot is essential. When using Azure OpenAI and Copilot Integration for Analytics Teams, ensure that AI models respect RLS policies. When a user asks Copilot to “show me all patient encounters,” the AI should only retrieve and display encounters the user is authorised to see.

This requires passing user context to Azure OpenAI through your application layer. When your analytics application calls OpenAI APIs, include the user’s identity and ward assignments in the system prompt. This ensures that any data returned by the AI model respects the user’s access restrictions.

Implement governance guardrails around AI-generated insights. If Copilot generates a summary of psychiatric ward data for a user who shouldn’t have access, your RLS policies have been bypassed. Regularly audit AI model outputs to ensure they respect security boundaries.

Deployment and Change Management

Deploying RLS to production requires careful planning. Start by deploying to a staging environment that mirrors production. Run your full test suite and have ward managers verify that access is correct. Document the exact procedures and scripts you’ll execute in production.

Schedule the deployment during a maintenance window when non-essential analytics access can be paused. Inform users that dashboards may be temporarily unavailable during the deployment. Have a rollback plan: if something goes wrong, you should be able to disable RLS policies quickly without losing data.

Execute the deployment in phases. First, deploy the security predicate functions and tables without enabling the security policy (use STATE = OFF). This allows you to test without blocking access. Then, enable the policy and monitor for issues. If problems arise, you can quickly disable it.

After deployment, monitor Fabric audit logs closely for the first week. Look for unexpected access denials or errors. Communicate with users about the RLS implementation and explain that they may see different data in dashboards based on their role.

Best Practices and Recommendations

Based on successful RLS implementations in healthcare environments, follow these best practices:

Principle of Least Privilege: Grant users access only to the wards and data they need to perform their role. Regularly audit access and remove unnecessary permissions.

Separation of Duties: Ensure that the person updating UserWardMapping is different from the person who creates security policies. This prevents a single person from granting themselves inappropriate access.

Documentation: Maintain clear documentation of your RLS architecture, policies, and access mappings. This is essential for compliance audits and helps new team members understand the system.

Performance Optimisation: Monitor query performance after implementing RLS. Use indexes and materialised views to ensure RLS doesn’t significantly impact dashboard load times.

Regular Testing: Test RLS quarterly to ensure it’s functioning correctly. Simulate role changes and verify that access is updated appropriately.

Compliance Integration: Ensure your RLS implementation aligns with Australian Privacy Principles, Health Records Act requirements, and any industry-specific standards like HIPAA (if applicable to your organisation).

For organisations implementing comprehensive data governance alongside RLS, exploring the Best Microsoft Fabric Tools and Integrations for 2026 can identify complementary tools for data cataloguing, lineage tracking, and access governance.

Conclusion and Next Steps

Implementing row-level security in Microsoft Fabric for multi-ward healthcare dashboards is a critical step toward protecting patient privacy and maintaining compliance with Australian data protection regulations. By following this tutorial, you’ve created a robust security architecture that automatically restricts data visibility based on user roles and ward assignments.

Your next steps should include conducting a comprehensive security audit of your current analytics environment, identifying all sensitive data elements that require RLS protection, and developing a detailed implementation roadmap aligned with your organisation’s change management processes. Engage your compliance, privacy, and security teams early to ensure the implementation meets all regulatory requirements.

Consider how RLS integrates with your broader data governance strategy. Fabric provides powerful capabilities for data discovery, lineage tracking, and access governance through Microsoft Purview, which should work in concert with your RLS implementation. As your analytics maturity grows and you adopt more advanced AI-powered analytics, ensure that security policies evolve accordingly.

For healthcare organisations planning comprehensive modernisation of their analytics platforms, Agile Insights provides end-to-end Fabric implementation services, including security architecture design, RLS policy development, and ongoing governance support. Our Microsoft-certified accelerators for healthcare analytics can significantly accelerate your implementation timeline and ensure best practices are embedded from the start.

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