In the SAP HANA database, Large Objects (LOBs) are unstructured data types such as images, videos, or documents. The importance of LOBs in HANA, particularly regarding their disk size, is significant for performance, storage management, and application development.
1. Definition of LOBs
LOBs, or Large Objects, refer to unstructured data types
that include items such as pictures, PDFs, and XML content1. They are
characterized by their capability to be quite large, which necessitates special
considerations in terms of storage and performance within databases like SAP
HANA4.
2. Disk Size Limitation
In SAP HANA, the current maximum size for a LOB is 2 GB2.
This limitation is critical as it influences how data is managed within the
database and affects the strategies for data storage and retrieval employed by
application developers.
3. Storage of LOBs in HANA
SAP HANA can store large binary objects (LOBs) such as
images or videos on disk, rather than inside column or row structures in main
memory3. This distinction is vital for performance optimization, as storing
large objects on disk allows for more efficient use of memory resources in main
operations.
4. Impact on Performance
The way LOBs are managed in SAP HANA—their storage on
disk instead of main memory—has implications for startup times and takeover
processes5. As LOBs can occupy considerable storage space, their management
directly affects the overall efficiency of data access patterns in applications
utilizing HANA.
5. Application Development Considerations
Understanding the size and nature of LOBs is essential
for application developers working with SAP HANA6. They must consider these
aspects when designing data models and structures to ensure optimal performance
and adherence to size constraints for LOB storage.