This simulation demonstrates how SAP HANA uses delta storage and merge operations to efficiently handle writes in column-based tables.
Main Storage (Column Format)
8 RecordsDelta Storage (Row Format)
0 Records
Merge at: 5
How Queries Work
Main Storage
8
+
Delta Storage
0
=
Combined Result
8
When a query executes, SAP HANA transparently combines results from both stores to provide a complete view.
Performance Metrics
Query Response Time
10 ms
Increases as Delta grows
Memory Usage
100 MB
Row format uses more memory
Compression Ratio
4.0x
Columns compress better than rows
Advantages of Delta Storage
- Fast write operations (inserts, updates, deletes)
- Avoids decompressing Main Storage for every write
- Optimized for high transaction throughput
- Supports both OLTP and OLAP workloads efficiently
- Transparent to applications and end users
When Delta Merge Occurs
- When Delta Storage reaches size threshold
- During scheduled system maintenance windows
- Triggered manually by database administrators
- Based on workload patterns and system resources
- Can be fine-tuned for specific workload requirements