Data Management Using B* Trees 

The SAP DB data management architecture ensures efficient data storage on disks and fast data access. The SAP DB database system performs automatic load balancing, which makes reorganizations unnecessary. The data areas can be extended online.

Structures and algorithms are available that are required for realizing an efficient I/O strategy, and that make reorganizations unnecessary. The data management algorithms have the following characteristics:

·        Sort data on SELECT (Table Access (SELECT) using B* Trees)

·        Sort data on INSERT (Table Access (INSERT) using B* Trees)

·        UPDATE data in place (Table Access (UPDATE) using B* Trees)

·        DELETE data in place (Table Access (DELETE) using B* Trees)

For this data management, the database system uses the following logical storage structures:

·        Primary tables (with primary keys and secondary keys)

·        Secondary key tables (data of the secondary keys)

·        B* Tree
There are build B* trees for the following tables (B* Trees for Tables): primary tables and secondary key tables
For tables with LONG columns (data type LONG also known as binary large objects (BLOBs)) there is a special data processing using B* trees for tables with LONG columns.