Schema Mapping in SAP HANA

• Schema mapping is required when moving SAP HANA objects from one system to another system, say from Development system to Test System, or Test System to Production System. 

• To understand Schema mapping, we first have to understand schema, authoring schema and physical schema. Let's check them one by one. 

The concept of Authoring schema and Physical schema:

What is schema?

• A database schema is a way to logically group objects such as tables, views, stored procedures etc. You can think of a schema as a container of objects.

Authoring schema:

• An authoring schema (logical schema) is the database schema used in the design time views. For example, this is the database schema that is used in the content development system. 

Example:

• Suppose we are developing some modeling views in Development System (DEV). The schema present in the Development system is DEV_SCHEMA, which contains all the required tables. The tables in the schema DEV_SCHEMA is used in modeling views creation. So DEV_SCHEMA is Authoring Schema.

Physical schema:

• When contents are moved to a different system, the target system might contain a different schema name. The schema available in the target system, which contains required tables is called physical schema. 

Example:

• Suppose the content created in the Development System (DEV) is moved to Production System (PROD).
• It is very likely that the schema name is different in the customer system. Say for example the required tables which were present in DEV_SCHEMA in the development system, are present in a schema PROD_SCHEMA in the production system.
• In this case, the physical schema is PROD_SCHEMA.