System Defined Schemas in Hana

System Defined Schema: 
These schemas are delivered with the SAP HANA database and contains HANA system information. There are system schemas like _SYS_BIC, _SYS_BI, _SYS_REPO, _SYS_STATISTICS etc.

System Generated Schemas:

 

SYS_BIC: 
This schema contains all the columns views of activated objects. When the user activates the Attribute View/Analytic View/Calculation View/Analytic Privilege /Procedure, the respective run-time objects are created under _SYS_BIC/ Column Views.

_SYS_REPO: 
Whatever the objects are there in the system is available in repository. This schema contains the list of Activated objects, Inactive Objects, Package details and Runtime Objects information etc.
 Also _SYS_REPO user must have SELECT privilege with grant option on the data schama.
Read more about "GRANT SELECT PRIVILEGE ON _SYS_REPO" 

_SYS_BI: 
This schema stores all the metadata of created column Views. It contains the tables for created Variables, Time Data (Fiscal, Gregorian), Schema Mapping and Content Mapping tables.

_SYS_STATISTICS: 
This schema contains all the system configurations and parameters.

_SYS_XS: 
This schema is used for SAP HANA Extended Application Services.

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