SAP C_HANADEV_18 Exam Questions

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.

To produce sales value for the month using sales order line items (sales price per item x quantity sold), you can use a calculated column of a calculation view that performs the multiplication of the two columns and applies a transparent filter and a non-equijoin to restrict the data to the desired month. A transparent filter is a filter condition that is applied to the data source of a view node and is propagated to the subsequent nodes. A non-equijoin is a join condition that uses operators other than equality, such as greater than, less than, or between. For example, you can use a transparent filter to filter the sales order line items by the month of the order date, and then use a non-equijoin to join the sales order line items with the sales price table by the order date and the valid from and valid to dates of the sales price.Reference:Transparent Filters,Non-Equijoins,Create Calculated Columns.

To specify the target currency for currency conversion in calculation views, you can use one of the following methods:

In a column: You can associate the measure with an attribute column that contains the target currency code. For example, if you have a table that stores the sales amount and the currency code for each transaction, you can use the currency code column as the target currency for the sales amount measure.

With an input parameter: You can create an input parameter that allows the user to select or enter the target currency code at runtime. For example, if you want to display the sales amount in different currencies based on the user's preference, you can use an input parameter as the target currency for the sales amount measure.

With a fixed value: You can associate the measure with a fixed currency code that is available in the currency table. For example, if you want to display the sales amount in a single currency, such as USD, you can use a fixed value as the target currency for the sales amount measure.Reference:Associate Measures with Currency,How to perform Currency Conversion in SAP HANA,Implementing Currency Conversion.

According to the SAP HANA SQLScript Reference1, database procedures are subroutines that can be called from SQL statements or other database procedures. Database procedures can have the following characteristics:

Database procedures can have both input and output parameters; however, a parameter CANNOT be both input and output. Input parameters are used to pass values to the procedure, while output parameters are used to return values from the procedure. A parameter can be either scalar or table type, depending on the data type and cardinality. A parameter cannot be both input and output, because this would create ambiguity and inconsistency in the parameter passing mechanism. For example, you cannot declare a parameter as IN OUT, or assign a value to an input parameter, or read a value from an output parameter.For more information on database procedure parameters, see [Parameters of Database Procedures]2.

Database procedures can have several output parameters, and a mix of both scalar and table types is possible. Output parameters are used to return values from the procedure to the caller. A procedure can have zero or more output parameters, depending on the purpose and logic of the procedure. Output parameters can be either scalar or table type, depending on the data type and cardinality. A procedure can have a mix of both scalar and table output parameters, as long as they are compatible with the caller's expectations and syntax. For example, you can use a SELECT statement with INTO clause to assign values to scalar output parameters, or use a SELECT statement with RESULT clause to return a table output parameter.For more information on database procedure output parameters, see [Output Parameters of Database Procedures]3.

If, in the database procedure header, you use the READS SQL DATA option, then INSERT statements are prohibited; however, dynamic SQL is allowed. The READS SQL DATA option is used to indicate that the procedure only reads data from the database, and does not modify or write any data. This option is useful for performance optimization and security enforcement, as it allows the database to apply certain optimizations and checks to the procedure. However, this option also imposes some restrictions on the procedure, such as prohibiting any INSERT, UPDATE, DELETE, or MERGE statements, or any other statements that modify the database state. Dynamic SQL, which is SQL code that is constructed and executed at run time, is still allowed, as long as it does not violate the READS SQL DATA option.For more information on the READS SQL DATA option, see [Procedure Header Options]4.

If, in the database procedure header, you use the SQL SECURITY INVOKER option, then only the owner of the procedure can start it. The SQL SECURITY INVOKER option is used to indicate that the procedure is executed with the privileges of the user who invokes the procedure, rather than the privileges of the user who created the procedure. This option is useful for security enforcement and access control, as it allows the database to apply the appropriate authorization checks and restrictions to the procedure. However, this option does not affect who can start the procedure, as this is determined by the GRANT EXECUTE statement, which grants the execute privilege on the procedure to a specific user or role. The SQL SECURITY INVOKER option only affects how the procedure is executed, not who can execute it.For more information on the SQL SECURITY INVOKER option, see [Procedure Header Options]4.