Earlier in HANA we used to have Information models(Attr, Ana, Cal Views) and for procedural capabilities like Looping, chaining, conditioning the SQL script with procedures for more complex scenarios and orchestration. Since there are life-cycle challenges with these HANA objects to be consumed in ABAP, SAP Introduced Semantically rich data model called CDS as a substitute of IMs and AMDP as a substitute of Procedures. So AMDP is a SQL script procedure, which can be used to squeeze the DB for its last strength and implement more complex logic.