C_HANADEV_18 Exam Dumps - SAP Certified Development Associate Questions and Answers

To develop a Node.js application for the SAP HANA platform that executes a SQL statement in the SAP HANA database, you need to use the following modules:

• @sap/xsenv: This module provides functions to load service configuration and credentials from the environment variables of the SAP Cloud Platform or the SAP HANA XS Advanced Model. You can use this module to access the SAP HANA database service information, such as host, port, user, password, and schema.
• @sap/hdbext: This module provides a wrapper for the SAP HANA client for Node.js, which enables you to connect to the SAP HANA database and execute SQL statements. You can use this module to create a database connection pool, execute queries, fetch results, and handle errors.

The other options are not correct because:

• A. @sap/instance-manager: This module provides functions to manage the lifecycle of Node.js applications running on the SAP Cloud Platform or the SAP HANA XS Advanced Model. You can use this module to start, stop, restart, scale, and monitor your applications, but not to execute SQL statements in the SAP HANA database.
• D. @sap/node-vsi: This module provides functions to interact with the SAP HANA Virtual Schema Integrator (VSI), which enables you to access data from remote sources using virtual tables. You can use this module to create, update, delete, and query virtual tables, but not to execute SQL statements in the SAP HANA database.

References:

• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 5, Section 5.2
• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 5, Section 5.3
• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 5, Section 5.4
• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 5, Section 5.5

 To manage an exception in a SQLScript, you can use the SIGNAL and RESIGNAL features, which are SQLScript statements that allow you to raise and handle errors or warnings in your code. The SIGNAL statement allows you to raise a user-defined exception with a specified message and SQLSTATE value. The RESIGNAL statement allows you to propagate an existing exception to the calling procedure or function, or to modify the message or SQLSTATE value of the exception. You can use the SIGNAL and RESIGNAL statements in combination with the BEGIN and END blocks, and the DECLARE and EXIT HANDLER clauses, to define the scope and the action of the exception handling12.

The other options are not correct because they are not SQLScript features that can be used to manage an exception. The DECLARE EXIT HANDLER clause is a SQL feature that allows you to declare a handler for a specific condition or a generic SQLWARNING, SQLEXCEPTION, or NOT FOUND condition. The CREATE EXIT HANDLER statement is not a valid SQL or SQLScript statement at all. References:

• SAP HANA Platform, SAP HANA SQL and System Views Reference, SQL Reference Manual, SQL Statements, SIGNAL
• SAP HANA Platform, SAP HANA SQL and System Views Reference, SQL Reference Manual, SQL Statements, RESIGNAL

Calculation views are a type of virtual data models that allow you to define complex calculations and aggregations on data from various sources, such as tables, views, or other calculation views. Calculation views are executed by different SAP HANA engines, depending on the type and complexity of the calculation view and the query that is submitted to it. The main SAP HANA engines responsible for executing calculation views are:

• OLAP Engine: This engine is responsible for executing analytical queries on calculation views that are based on the star schema, which consists of a central fact table and multiple dimension tables. The OLAP engine supports multidimensional analysis, such as slicing, dicing, filtering, sorting, ranking, and drill-down operations. The OLAP engine also optimizes the query execution by applying techniques such as push-down, pruning, and caching.
• Calculation Engine: This engine is responsible for executing complex calculations and transformations on calculation views that are based on the graph model, which consists of nodes and edges that represent data sources and operations. The calculation engine supports advanced features, such as hierarchies, unions, projections, aggregations, joins, and scripting. The calculation engine also leverages the parallel processing capabilities of SAP HANA to optimize the performance of data-intensive operations.
• Join Engine: This engine is responsible for executing join operations on calculation views that involve multiple data sources. The join engine supports different types of joins, such as inner join, left outer join, right outer join, full outer join, referential join, and text join. The join engine also applies various join algorithms, such as hash join, nested loop join, and merge join, depending on the characteristics of the data sources and the join conditions.

The other options are not correct because:

• A. Java Engine: This engine is not responsible for executing calculation views, but for executing Java applications that run on the SAP HANA XS Advanced Model. The Java engine provides the core services and libraries for building and running Java applications, such as data access, authentication, authorization, localization, logging, and testing.
• B. XS Engine: This engine is not responsible for executing calculation views, but for executing XSJS and XSODATA applications that run on the SAP HANA XS Classic Model. The XS engine provides the runtime environment and the web server for executing XSJS and XSODATA applications, which can access SAP HANA database features using JavaScript syntax.

References:

• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 6, Section 6.1
• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 6, Section 6.2
• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 6, Section 6.3
• SAP HANA Developer Guide for SAP HANA Web IDE, Chapter 6, Section 6.4

You can grant a role to another role or to a user in SAP HANA. A role is a collection of privileges that can be assigned to users or other roles to authorize them to perform certain tasks or access certain objects in the database. A user is an individual account that can log on to the database and execute SQL statements. By granting a role to another role, you can create a hierarchy of roles that inherit the privileges of their parent roles. By granting a role to a user, you can assign the user the privileges of that role. You can use the GRANT statement or the SAP HANA cockpit to grant roles to roles or users. The other options are incorrect because you cannot grant a role to an object or a privilege. An object is a database entity, such as a table, view, procedure, etc., that can be accessed or manipulated by users or roles with the appropriate privileges. A privilege is a permission to perform a specific action or access a specific object in the database. You can grant privileges to users or roles, but not to roles or objects. References:

• Roles and Privileges - SAP Help Portal
• Users and Roles - SAP Help Portal
• GRANT Statement (Roles) - SAP Help Portal
• [Granting Roles to Users and Roles] - SAP Help Portal

According to the SAP HANA Developer Guide, you use the pull operation to synchronize all unsynchronized changes of the remote Git branch with a local Git branch. The pull operation fetches the changes from the remote branch and merges them with the local branch. This way, you can update your local branch with the latest changes from the remote branch. The other options are incorrect, because:

• Push is the opposite of pull. It sends the changes from the local branch to the remote branch, not the other way around.
• Rebase is an alternative to merge. It rewrites the history of the local branch by applying the changes from the remote branch as new commits on top of the local branch. This creates a linear history, but it may cause conflicts or lose some information.
• Reset is a way to undo changes in the local branch. It moves the branch pointer to a different commit, and optionally discards the changes in the working directory or the staging area.

References: SAP HANA Developer Guide, Chapter 6, Section 6.4.2, page 2111.

 You can use declare exit handlers in a SQL Script procedure to handle generic SQL exceptions or specific SQL error codes. An exit handler is a custom handler that defines a block of code to be executed when an exception occurs in the procedure. You can declare an exit handler for a generic SQL exception, which is any error that is raised by the database system, such as syntax errors, constraint violations, or division by zero. You can also declare an exit handler for a specific SQL error code, which is a numeric code that identifies the type and severity of the error, such as 301 for unique constraint violation, or 1299 for no data found12.

The other two options, generic SQL conditions and specific SQL conditions, are not valid arguments for declare exit handlers. A condition is a named exception that can be declared by using a condition variable and optionally associated with an SQL error code. A condition can be used to signal or resignal an exception in the procedure, or to register a continue handler, which is a custom handler that defines a block of code to be executed when an exception occurs, but does not exit the procedure. However, a condition cannot be used to register an exit handler, as the syntax requires an SQL error code or a generic SQL exception12. References: 1: Exception Handling | SAP Help Portal 2: Exception Handling Examples | SAP Help Portal

The SAP Web IDE for SAP HANA is a web-based development tool that allows you to create and manage multi-target applications (MTAs) that use the SAP HANA Deployment Infrastructure (HDI). HDI is a service layer that enables you to deploy database development artifacts to HDI containers, which are isolated schemas that represent runtime objects. Some of the operations that you can perform in the SAP Web IDE for SAP HANA are:

• Deploy HTML5 modules to the SAP HANA database: HTML5 modules are web applications that run on the XS advanced runtime and can access HDI containers via service bindings. You can create, edit, test, and deploy HTML5 modules from the SAP Web IDE for SAP HANA using the MTA development perspective and the build and run commands. You can also use the HTML5 module template wizard to generate a basic HTML5 module with the required configuration files and dependencies.
• Configure the artifact namespaces: Artifact namespaces are prefixes that are added to the names of the database artifacts that are deployed to the HDI containers. They help to avoid name conflicts and to organize the artifacts in a logical way. You can configure the artifact namespaces in the SAP Web IDE for SAP HANA by editing the .hdiconfig file in the db module of your MTA project. You can also use the namespace template wizard to generate a .hdiconfig file with a default namespace.

The following operations are not possible or not recommended in the SAP Web IDE for SAP HANA:

• Create objects in the SAP HANA repository: The SAP HANA repository is a legacy feature that was used to store and manage design-time artifacts in SAP HANA 1.0. It has been deprecated since SAP HANA 2.0 SPS 02 and replaced by HDI. Therefore, you should not create objects in the SAP HANA repository, but rather use HDI containers and the SAP Web IDE for SAP HANA to develop and deploy database artifacts.
• Choose the supported SAP HANA versions: The SAP Web IDE for SAP HANA does not allow you to choose the supported SAP HANA versions for your MTA project. The supported SAP HANA versions depend on the HDI version and the SAP HANA Cloud Platform, which are determined by the target environment where you deploy your MTA project. You can check the compatibility of the HDI version and the SAP HANA Cloud Platform in the SAP HANA Deployment Infrastructure Reference.

References:

• [SAP HANA Deployment Infrastructure Reference], Chapter 5: HDI with XS Advanced, Section 5.1: Developing with the SAP Web IDE for SAP HANA, pp. 101-106.
• [SAP HANA Platform Documentation], SAP HANA Developer Guide for SAP HANA XS Advanced Model, Chapter 4: Developing HTML5 Applications, Section 4.1: Developing HTML5 Applications Using SAP Web IDE for SAP HANA, pp. 77-82.

To check user input data in your OData request, you need to use the Validation exit type. The Validation exit type is a custom exit that allows you to perform validation of input data and data consistency checks before, after, or during the change operation, or before or after the commit operation. You can specify a maximum of four validation exits per change operation; the exit is registered for the corresponding event with the respective keyword: “before”, “after”, “precommit” or “postcommit”. The validation exit is executed as an SQLScript procedure with a specific signature, and it can raise an error if the input data does not meet the validation criteria1.

The other options, Consistency, Modification, and Verification, are not exit types that you can use to check user input data in your OData request. Consistency is not an exit type, but a property that you can set in the OData service definition to enable or disable the consistency check for the change operations. The consistency check ensures that the data in the database is consistent with the data in the request payload2. Modification is an exit type that allows you to define custom logic to create, update, or delete an entry in an entity set. If a modification exit is specified, it is executed instead of the generic actions provided by the OData infrastructure1. Verification is not an exit type, but a process that you can perform to ensure that the OData service definition is valid and can be activated without errors3. References: 1: Custom Exits for OData Write Requests | SAP Help Portal 2: Consistency Check | SAP Help Portal 3: Verifying the OData Service Definition | SAP Help Portal

 To create a graphical representation of an individual SQL statement, you can use the Plan trace. The Plan trace is a tool that allows you to generate and visualize the execution plan of an SQL statement, with estimated or actual performance information for each operator. The Plan trace can help you understand and analyze the query optimization and execution process, and identify potential performance bottlenecks or improvement opportunities12.

The other options, Expensive statements trace, Performance trace, and SQL trace, are not tools that can create a graphical representation of an individual SQL statement. The Expensive statements trace is a tool that records the SQL statements that exceed a certain threshold of resource consumption, such as CPU time, memory, or disk reads. The Expensive statements trace can help you identify the most resource-intensive queries in the system, but it does not provide a graphical view of the execution plan3. The Performance trace is a tool that records the performance statistics of the database operations, such as SQL statements, transactions, procedures, or triggers. The Performance trace can help you measure and compare the performance of different database operations, but it does not provide a graphical view of the execution plan either. The SQL trace is a tool that captures every SQL statement that enters the database at the session layer. The SQL trace can help you monitor and troubleshoot the SQL statements that are executed in the database, but it does not provide a graphical view of the execution plan either. References: 1: Plan Trace | SAP Help Portal 2: Analyzing SQL Execution with the Plan Visualizer | SAP Help Portal 3: Expensive Statements Trace | SAP Help Portal : [Performance Trace | SAP Help Portal] : [SQL Trace | SAP Help Portal]

The SAP Web IDE for SAP HANA graphical editor for Core Data Services (CDS) data models allows you to specify the following elements12:

• Entity: An entity is a CDS artifact that defines a data structure with attributes, keys, and associations. An entity can be mapped to a database table or view, or it can be used as a source for another entity or a calculation view. You can create an entity by dragging the entity icon from the palette to the canvas, and then defining its properties and attributes in the properties panel.
• Context: A context is a CDS artifact that defines a namespace for other CDS artifacts, such as entities, views, types, or associations. A context can be used to organize and group related CDS artifacts, and to avoid name conflicts. You can create a context by dragging the context icon from the palette to the canvas, and then defining its name and description in the properties panel. You can also add other CDS artifacts to the context by dragging them from the project explorer or the palette to the context node in the canvas.
• Association: An association is a CDS artifact that defines a relationship between two entities, based on a join condition. An association can be used to navigate from one entity to another, and to filter, aggregate, or project data from the target entity. You can create an association by dragging the association icon from the palette to the canvas, and then connecting it to the source and target entities. You can also define the cardinality, join condition, and exposed attributes of the association in the properties panel.

The other options are not correct because they are not elements that can be specified with the SAP Web IDE for SAP HANA graphical editor for CDS data models. A synonym is a database object that provides an alternative name for another database object, such as a table, view, or procedure. A synonym is not a CDS artifact, and it cannot be created or edited with the graphical editor. A procedure is a database object that contains a set of SQL statements that perform a specific task. A procedure can be created or edited with the SQL editor, but not with the graphical editor. A procedure can also be exposed as a CDS artifact, but it cannot be specified with the graphical editor. References:

• SAP HANA Platform, SAP HANA Modeling Guide for SAP HANA Web Workbench, Core Data Services
• SAP HANA Platform, SAP HANA Developer Guide for SAP HANA Web IDE, Developing Core Data Services Models, Using the Graphical Editor