Go Up to Data Definition Guide
The Change Views™ feature uses InterBase multigenerational architecture to capture changes to data. This feature allows you to quickly answer the question, "What data has changed since I last viewed it?"
Previously it involved triggers, logging, and/or transaction write-ahead log scraping. This was time-consuming for the developer and affected the database performance for a certain transaction load or change volume. Now with Change Views, there is no performance overhead on existing transactions because it maintains a consistent view of changed data observable by other transactions.
The Change Views mechanism is not dependent on its own underlying data, but is based on data already stored for existing base tables or views derived from base tables. This implicit view mechanism is temporal based and returns data that have changed since the prior transaction in which the implicit view was observed.
Change Views can be subscribed to (Create Subscriptions to Implement Change Views) in order to view data that has changed across database connections. The effect is a long-lived transaction spanning multiple database connections.
- Specifically, the subscription tracks all row inserts, updates, and deletes to one or more tables at a column-level granularity over a disconnected, extended period of time.
- The InterBase SQL query language is modified to search on columns where data has changed since the prior observation.
- These data changes are tracked at a column granularity.
- Getting Started with Change Views
- Creating Subscriptions to Change Views
- Statement Execution
- Change Views API Support
- Change Views SQL Language Support
- Metadata Support
- Ad-hoc Subscriptions and SQL Language Support
- Change Views Requirements and Constraints
- Change Views Glossary