SAP HANA is technically based on a relational database management system (RDBMS). Such a database management system organizes and controls the data in a database (DB).
In simple terms, a database is made up of a large number of tables. In these tables, data or data records are stored in rows. SAP HANA uses this line-oriented database technology, but at the same time it uses the column-oriented approach that is common in in-memory databases.
The SAP HANA database management system ensures that analyses and transactions can be carried out in parallel - the unique selling point and great advantage of SAP HANA. Transactional and analytical data come from a single source. The basis is therefore a common data copy.
For this purpose, the database management system connects the so-called OLAP and OLTP landscapes in the in-memory database.
OLAP stands for Online Analytical Processing, OLTP for Online Transaction Processing. These methods involve the analysis and transaction of data in real time.
In an in-memory database, the data does not have to be temporarily copied from the hard disk to a working memory, as is usually the case. Instead, they are stored directly in the working memory. The main memory thus serves as a data storage.
Because memory is less well protected against possible data loss than hard disks, in-memory memory uses various methods to be as reliable as hard disks.
SAP HANA also ensures this "persistence": both in terms of data availability and in terms of data consistency and integrity.