General Differences 
Logical database structure
There are basic differences between the logical database structures of the database systems Oracle Version 7 and SAP DB Version 7.3.
- From a logical point of view, an Oracle database consists of tablespaces, segments, extents, blocks, tables, and data records.
- From a logical point of view, SAP DB consists basically of the tables in the
database catalog and the
user data in the form of data records.
All Oracle statements referring to the administration of tablespaces, segments, extents, or blocks are therefore meaningless in SAP DB.
Consistent reading/locking
The consistent reading offered by Oracle can be achieved in SAP DB by using
locks in isolation level >= 2 (you will find information on the isolation level in
CONNECT statement).
Oracle allows an unlimited number of exclusive row locks. In SAP DB, an escalation takes effect from a certain number of row locks; i.e., the whole table will be locked. The time of escalation depends on the defined lock list size.
Database procedures/triggers
In Oracle, database procedures, DB functions, and triggers are defined in PL/SQL, a language similar to ADA.
In SAP DB,
database procedures and
triggers are defined in a language similar to C.
Database objects and their schemas
Database users can only create or delete SAP DB database objects in or from their own schemas, or create database objects that are not assigned to a particular user (index, for example). It is not possible to create database objects in the schema of another user.
DBA users and privileges
In contrast to Oracle,
DBA users in SAP DB are also subject to the privileges concept and cannot execute DDL statements (such as CREATE INDEX) or DML statements (such as DELETE) for which they have not received the corresponding privileges.