In SAP HANA system, can someone help me to understand use of Persistence layer in SAP HANA? Why do we use it?
In SAP HANA, Persistence layer is used for handling all operational and transaction data to take secure backup and restoring data incase of corruption or database crash. It provides use of Save point which can be used for restoring data.
With use of concept of persistence layer of SAP’s relational database, it ensures the successful data restores. Besides managing log data on the disk, HANA’s persistence layer allows read and write data operations via all storage interfaces.
Persistence layer in HANA ensures that database can be restored to the most recent committed state after a restart or after a system crash and transactions are executed completely or completely undone. SAP HANA Persistent Layer is part of Index server and it has data and transaction log volumes for HANA system and in-memory data is regularly saved to these volumes. There are services in HANA system that has their own persistence. It also provides save points and logs for all the database transactions from the last save point.