ABAP ON HANA: cds views and amdp's usage.

[shadab_sk]

Hi experts,

I am new to abap on hana...I want to understand, why there is a need to have CDS Views as similar column views(attribute, analytic, calculations ) exists at HDB level..we can consume these views in abap code...Similarly while we can create procedures using HANA studio, why there is a need to have AMDP's.

Thank you.

[former_member184111]

Hi Shadab,

There are two approached for achieving 'Code Pushdown' i.e. executing expensive code at DB level instead of application server.

1. Bottom Up Approach-- Here the coding is done at DB level for e.g. HANA Stored procedures, Scripted calculation views or any view created in HANA Studio. These artifacts are then consumed in ABAP code using Proxies. For procedures there are DB proxies and to consume HANA view in ABAP there are external views created in ABAP AS.

2. Top Down- here coding is done at ABAP AS and no dependent objects are there in HANA. You can say AMDP replaces Procedure + DB Proxies and ABAP CDS replaces HANA View + External view.

The top down approach has two main benefits, first-objects are created in AS ABAP only so only 1 transport is required. In case of bottom up there is an object created in HANA and related object in ABAP so two transports which may cause issues if one object/transport is missed by mistake.

Second-Top down code can be made DB independent, i.e. you can put checks for carious DB and adjust code to run on all supported DBs where as if coding at DB it is specific.

Hope it help!!!

Anubhav