Open SQL – These statements are a subset of standard SQL. It consists of DML command (Select, Insert, Update, Delete). It can simplify and speed up database access. Buffering is partly stored in the working memory and shared memory. Data in buffer is not always up-to-date.

Native SQL – They are loosely integrated into ABAP. It allows access to all functions containing programming interface. They are not checked and converted. They are sent directly to the database system. Programs that use Native SQL are specific to the database system for which they were written. For e.g. to create or change table definition in the ABAP.