Pass C_HANADEV_18 Exam Guide

To exclusively use declarative logic in an SQL Script procedure, you can use TABLE variables and MAP_REDUCE functions. TABLE variables are variables that store intermediate results of SQL queries in a tabular format. You can use TABLE variables to define data transformations and data flows without using imperative statements or side effects1. MAP_REDUCE functions are functions that apply a map function to each row of a table and then aggregate the results using a reduce function. You can use MAP_REDUCE functions to implement complex algorithms and calculations in a declarative way2.

The other two options, COMMIT statement and IF condition, are not operators that can be used to exclusively use declarative logic in an SQL Script procedure. COMMIT statement is a statement that ends a transaction and makes all changes permanent in the database. You cannot use COMMIT statement in a declarative logic, as it is an imperative statement that has a side effect3. IF condition is a condition that executes a block of code based on a boolean expression. You cannot use IF condition in a declarative logic, as it is an imperative construct that introduces control flow4. References: 1: TABLE Variables | SAP Help Portal 2: MAP_REDUCE Function | SAP Help Portal 3: COMMIT Statement | SAP Help Portal 4: IF Statement | SAP Help Portal

 According to the SAP HANA SQLScript Reference, the following statements can be used when implementing transaction management logic in SQLScript using savepoints:

• Savepoint: Creates a savepoint with a specified name within the current transaction. A savepoint marks a point in the transaction that can be rolled back to without affecting the rest of the transaction. For example, SAVEPOINT sp1;
• Rollback to savepoint: Rolls back the current transaction to the specified savepoint. All changes made after the savepoint are undone, but the transaction remains active. For example, ROLLBACK TO SAVEPOINT sp1;
• Release savepoint: Releases the specified savepoint and all subsequent savepoints. The released savepoints are no longer valid and cannot be rolled back to. For example, RELEASE SAVEPOINT sp1;

The other options are incorrect, because:

• Reverse savepoint is not a valid statement in SQLScript. There is no such statement in the SAP HANA SQLScript Reference.
• Alter system savepoint is not a statement that can be used in SQLScript, but a statement that can be used in SQL. It triggers a savepoint operation for the entire database system, not for a specific transaction. It is used for administrative purposes, such as backup and recovery, not for transaction management logic.

References: SAP HANA SQLScript Reference, Chapter 6, Section 6.4.2, page 2111.

To complete the navigation definition from the customer entity set to the corresponding sales orders, you need to insert an association statement between the two entity sets. An association defines a relationship between two entity sets based on a referential constraint, which specifies the foreign key and the principal key properties that link the entity sets. An association also defines the cardinality and the role names of the entity sets involved in the relationship1. In this case, the association statement should look something like this:

association Customer_Orders with referential constraint principal customer key CustomerID dependent Orders key CustomerID multiplicity “1” to “*”;

This statement defines an association named Customer_Orders that relates the customer entity set with the Orders entity set based on the CustomerID property. The principal role is assigned to the customer entity set, which means that each customer entity can have zero or more related Orders entities. The dependent role is assigned to the Orders entity set, which means that each Orders entity must have exactly one related customer entity2.

The other options are not correct because:

• Aggregation: This is a feature of calculation views that allows you to define measures and attributes for analytical queries. It is not related to OData service definitions3.
• Key specification: This is a clause that you use to define the key properties of an entity type in an OData service definition. It is not used to define navigation between entity sets1.
• Join condition: This is a clause that you use to specify how to join two tables or views in a SQL statement. It is not used to define navigation between entity sets4.

References: 1: OData Service Definition Language Syntax (XS Advanced) 2: OData Service-Definition Examples 3: Creating Calculation Views 4: SQL Reference Manual

An OData V2 service is a web service that exposes data from a data source, such as a SAP HANA database, in a standardized and interoperable format based on the OData protocol version 2.0. An OData V2 service consists of one or more entity sets, which are collections of entities of the same type. An entity is a data object that has properties and a unique key. An OData V2 service can also define associations between entity sets, which are relationships that specify how entities are related to each other. An OData V2 service can also define function imports, which are operations that can be invoked by the client to perform specific tasks.

An OData V2 service exposes a data model that describes the structure and semantics of the data and the operations that are supported by the service. The data model is represented in an XML document that conforms to the OData Metadata XML Schema. The data model contains information such as the entity types, the entity sets, the associations, the function imports, the namespaces, the annotations, and the service document.

To view the data model exposed by an OData V2 service, you need to append the $metadata system query option to the service URL. The $metadata system query option requests the metadata document of the service. For example, if the service URL is then the metadata document URL is The metadata document URL can be accessed by any HTTP client, such as a web browser, and it returns the XML representation of the data model.

The other options are incorrect because they are not system query options that can be used to view the data model exposed by an OData V2 service. $schema is not a valid system query option in OData V2. $service definition is a system query option in OData V4, not OData V2, and it requests the service definition document, which is a JSON document that describes the capabilities and annotations of the service. $format is a system query option that can be used to specify the desired format of the response, such as XML or JSON, but it does not request the data model of the service. References:

• SAP HANA Platform 2.0 SPS06: OData V2 Developer Guide, Section 1.1
• SAP HANA Platform 2.0 SPS06: OData V2 Developer Guide, Section 2.1
• SAP HANA Platform 2.0 SPS06: OData V2 Developer Guide, Section 2.6
• OData Version 2.0: Part 1 - Protocol, Section 2.2.6
• OData Version 2.0: Part 3 - CSDL, Section 1