C_ABAPD_2309 - SAP Certified Associate - Back-End Developer - ABAP Cloud

• Use public SAP APIs and SAP extension points. This rule ensures that the ABAP Cloud code is stable, reliable, and compatible with the SAP solutions and the cloud operations. Public SAP APIs and SAP extension points are the only allowed interfaces and objects to access the SAP platform and the SAP applications. They are documented, tested, and supported by SAP. They also guarantee the lifecycle stability and the upgradeability of the ABAP Cloud code1.
• Build ABAP RESTful application programming model-based services. This rule ensures that the ABAP Cloud code follows the state-of-the-art development paradigm for building cloud-ready business services. The ABAP RESTful application programming model (RAP) is a framework that provides a consistent end-to-end programming model for creating, reading, updating, and deleting (CRUD) business data. RAP also supports draft handling, authorization checks, side effects, validations, and custom actions. RAP exposes the business services as OData services that can be consumed by SAP Fiori apps or other clients2.

In ABAP SQL, an alias is a temporary name that can be assigned to a field or a database table in a query. An alias can be used to make the query more readable, to avoid name conflicts, or to access fields or tables with long names. An alias is created with the AS keyword and is only valid for the duration of the query1.

The following are examples of how to assign an alias to a field or a database table in ABAP SQL:

• B. field (from field list): A field is a column of a table or a view that contains data of a certain type. A field can be assigned an alias in the field list of a SELECT statement, which specifies the fields that are selected from the data source. For example, the following query assigns the alias name to the field carrname of the table scarr:

SELECT carrid, carrname AS name FROM scarr.

The alias name can be used instead of carrname in other clauses of the query, such as WHERE, GROUP BY, ORDER BY, and so on2.

• C. database table: A database table is a collection of data that is organized in rows and columns. A database table can be assigned an alias in the FROM clause of a SELECT statement, which specifies the data source that is selected from. For example, the following query assigns the alias c to the table scarr:

SELECT c.carrid, c.carrname FROM scarr AS c.

The alias c can be used instead of scarr in other clauses of the query, such as WHERE, JOIN, GROUP BY, ORDER BY, and so on3.

The following are not valid for assigning an alias in ABAP SQL:

• A. order criterion (from order by clause): An order criterion is a field or an expression that is used to sort the result set of a query in ascending or descending order. An order criterion cannot be assigned an alias in the ORDER BY clause of a SELECT statement, because the alias is not visible in this clause. The alias can only be used in the clauses that follow the clause where it is defined1.
• D. group criterion (from group by clause): A group criterion is a field or an expression that is used to group the result set of a query into subsets that share the same values. A group criterion cannot be assigned an alias in the GROUP BY clause of a SELECT statement, because the alias is not visible in this clause. The alias can only be used in the clauses that follow the clause where it is defined1.

References: 1: ALIASES - ABAP Keyword Documentation 2: SELECT List - ABAP Keyword Documentation 3: FROM Clause - ABAP Keyword Documentation

You would use Access Controls with CDS Views for the following reasons:

• A. Only the data corresponding to the user’s authorization is transferred from the database to the application layer. This is true because Access Controls allow you to define CDS roles that specify the authorization conditions for accessing a CDS view. The CDS roles are evaluated for every user at runtime and the system automatically adds the restrictions to the selection conditions of the CDS view. This ensures that only the data that the user is authorized to see is read from the database and transferred to the application layer. This improves the security and the performance of the data access1.
• C. You do not have to remember to implement AUTHORITY CHECK statements. This is true because Access Controls provide a declarative and centralized way of defining the authorization logic for a CDS view. You do not have to write any procedural code or use the AUTHORITY CHECK statement to check the user’s authorization for each data source or field. The system handles the authorization check automatically and transparently for you2.

The following reasons are not valid for using Access Controls with CDS Views:

• B. The system field sy-subrc is set, giving you the result of the authorization check. This is false because the system field sy-subrc is not used by Access Controls. The sy-subrc field is used by the AUTHORITY CHECK statement to indicate the result of the authorization check, but Access Controls do not use this statement. Instead, Access Controls use CDS roles to filter the data according to the user’s authorization2.
• D. All of the data from the data sources is loaded into your application automatically and filtered there according to the user’s authorization. This is false because Access Controls do not load all the data from the data sources into the application layer. Access Controls filter the data at the database layer, where the data resides, and only transfer the data that the user is authorized to see to the application layer. This reduces the data transfer and the memory consumption of the application layer1.

References: 1: Access Controls | SAP Help Portal 2: ABAP CDS - Access Control - ABAP Keyword Documentation