Working with Advanced SQL Server System Versioning (Temporal Tables)

Introduction

SQL Server System Versioning, also known as Temporal Tables, allows you to keep a history of data changes in your database. This guide explores advanced techniques for working with Temporal Tables, including sample code and examples.

1. Creating a Temporal Table

Learn how to create a Temporal Table that tracks data changes over time.

-- Create a Temporal Table
CREATE TABLE YourTable
(
    ID INT PRIMARY KEY,
    Name NVARCHAR(50),
    SysStartTime DATETIME2 GENERATED ALWAYS AS ROW START,
    SysEndTime DATETIME2 GENERATED ALWAYS AS ROW END,
    PERIOD FOR SYSTEM_TIME (SysStartTime, SysEndTime)
)
WITH (SYSTEM_VERSIONING = ON (HISTORY_TABLE = YourHistoryTable));
    

2. Querying Temporal Data

Explore techniques for querying historical and current data from Temporal Tables.

-- Querying Temporal Data
SELECT * FROM YourTable
FOR SYSTEM_TIME BETWEEN '2023-01-01' AND '2023-12-31';
    

3. Modifying Temporal Data

Understand how to insert, update, and delete data in Temporal Tables while maintaining historical records.

-- Modifying Temporal Data
INSERT INTO YourTable (ID, Name)
VALUES (1, 'NewData')
FOR SYSTEM_TIME ALL;
    

4. History Cleanup and Retention

Implement strategies for cleaning up historical data to control the size of the history table.

-- History Cleanup and Retention
ALTER TABLE YourTable
SET (SYSTEM_VERSIONING = OFF);

-- Perform cleanup operations
    

5. Advanced Use Cases

Advanced Temporal Table usage may involve schema changes, auditing, and data migration scenarios.

-- Advanced Temporal Table Usage
// Include advanced Temporal Table usage scenarios
// ...
    

Conclusion

SQL Server System Versioning provides a powerful way to track and manage historical data changes. By mastering techniques such as table creation, querying, data modification, history cleanup, and advanced use cases, you can harness the benefits of Temporal Tables for your data history and auditing needs.