C_ABAPD_2309 Exam Dumps - SAP Certified Associate Questions and Answers

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

String functions are expressions that can be used to manipulate character-like data in ABAP. String functions can be either predicate functions or non-predicate functions. Predicate functions are string functions that return a truth value (true or false) for a condition of the argument text. Non-predicate functions are string functions that return a character-like result for an operation on the argument text1.

The following string functions are predicate functions:

B. contains_any_of(): This function returns true if the argument text contains at least one of the characters specified in the character set. For example, the following expression returns true, because the text ‘ABAP’ contains at least one of the characters ‘A’, ‘B’, or ‘C’:

contains_any_of( val = ‘ABAP’ set = ‘ABC’ ).

D. matches(): This function returns true if the argument text matches the pattern specified in the regular expression. For example, the following expression returns true, because the text ‘ABAP’ matches the pattern that consists of four uppercase letters:

matches( val = ‘ABAP’ regex = ‘[A-Z]{4}’ ).

The following string functions are not predicate functions, because they return a character-like result, not a truth value:

A. find_any_not_of(): This function returns the position of the first character in the argument text that is not contained in the character set. If no such character is found, the function returns 0. For example, the following expression returns 3, because the third character of the text ‘ABAP’ is not contained in the character set ‘ABC’:

find_any_not_of( val = ‘ABAP’ set = ‘ABC’ ).

C. count_any_of(): This function returns the number of characters in the argument text that are contained in the character set. For example, the following expression returns 2, because there are two characters in the text ‘ABAP’ that are contained in the character set ‘ABC’:

count_any_of( val = ‘ABAP’ set = ‘ABC’ ).

References: 1: String Functions - ABAP Keyword Documentation

A metadata extension is a RESTful Application Programming object that can be used to organize the display of fields in an app. A metadata extension is a CDS view that annotates another CDS view with UI annotations, such as labels, icons, or facets. These annotations define how the data should be presented in the app, such as which fields should be shown on the object page, which fields should be editable, or which fields should be used for filtering or sorting. A metadata extension can also be used to add custom actions or validations to the app12. References: 1: Refine the Object Page with Annotations | SAP Tutorials 2: ABAP RAP : Enabling custom actions with a dialog for additional input fields | SAP Blogs

In RESTful Application Programming, the EML statement that retrieves an object is GET entity. The GET entity statement is used to read data of an entity instance from the database or the transaction buffer. The GET entity statement can specify the entity name, the entity key, and the entity elements to be retrieved. The GET entity statement can also use the IN LOCAL MODE addition to bypass the access control, authorization control, and feature control checks. The GET entity statement returns a single entity instance or raises an exception if no instance is found or multiple instances match the key.

The other EML statements are not used to retrieve an object, but have different purposes and effects. These statements are:

FIND entity: This statement is used to search for entity instances that match a given condition. The FIND entity statement can specify the entity name, the entity elements to be returned, and the condition to be applied. The FIND entity statement can also use the IN LOCAL MODE addition to bypass the access control, authorization control, and feature control checks. The FIND entity statement returns a table of entity instances or an empty table if no instances match the condition.

SELECT entity: This statement is used to query data of entity instances from the database or the transaction buffer. The SELECT entity statement can specify the entity name, the entity elements to be returned, and the filter, order, and aggregation options to be applied. The SELECT entity statement can also use the IN LOCAL MODE addition to bypass the access control, authorization control, and feature control checks. The SELECT entity statement returns a table of entity instances or an empty table if no instances match the query.

READ entity: This statement is not a valid EML statement, but an ABAP statement. The READ statement is used to access a single row of an internal table using the table index or the table key. The READ statement can also use the TRANSPORTING addition to specify which fields should be returned, and the INTO addition to specify the target variable. The READ statement returns a single row of the internal table or raises an exception if no row is found or multiple rows match the key.

References: GET ENTITY - ABAP Keyword Documentation, FIND ENTITY, ENTITIES - ABAP Keyword Documentation, SELECT ENTITY, ENTITIES - ABAP Keyword Documentation, READ - ABAP Keyword Documentation

 Core Data Services (CDS) are preferable to the classical approach to data modeling for several reasons, but two of them are:

They implement code pushdown. Code pushdown is the principle of moving data-intensive logic from the application server to the database server, where the data resides. This reduces the data transfer between the application server and the database server, which improves the performance and scalability of the application. CDS enable code pushdown by allowing the definition of semantic data models and business logic in the database layer, using SQL and SQL-based expressions1.

They transfer computational results to the application server. CDS allow the application server to access the data and the logic defined in the database layer by using Open SQL statements. Open SQL is a standardized and simplified subset of SQL that can be used across different database platforms. Open SQL statements are translated into native SQL statements by the ABAP runtime environment and executed on the database server. The results of the computation are then transferred to the application server, where they can be further processed or displayed2.

References: 1: ABAP - Core Data Services (ABAP CDS) - ABAP Keyword Documentation 2: Open SQL - ABAP Keyword Documentation

The response will be an activation error because the field names of the union do not match. This is because the field names of the union must match in order for the definition to be activated. The union operator combines the result sets of two or more queries into a single result set. The queries that are joined by the union operator must have the same number and type of fields, and the fields must have the same names1. In the given code, the field names of the union do not match, because the first query has the fields carrname, connid, cityfrom, and cityto, while the second query has the fields carrname, carrier_id, cityfrom, and cityto. The field connid in the first query does not match the field carrier_id in the second query. Therefore, the definition cannot be activated.

References: 1: UNION - ABAP Keyword Documentation

In ABAP SQL, the syntax to retrieve the association field of a CDS view is to use the @ sign followed by the association name and the field name, separated by a period sign (.). For example, to retrieve the association field _Airline-Name of a CDS view, the syntax is @_Airline.Name. This syntax allows the access to the fields of the target data source of the association without explicitly joining the data sources1. The other options are incorrect because they use the wrong symbols or formats to access the association field.

References: 1: Path Expressions - ABAP Keyword Documentation

The nested join is evaluated from the top to the bottom in the order of the ON conditions. This means that the join expression is formed by assigning each ON condition to the directly preceding JOIN from left to right. The join expression can be parenthesized implicitly or explicitly to show the order of evaluation. In this case, the implicit parentheses are as follows:

SELECT * FROM (a INNER JOIN (b INNER JOIN c ON b~c = c~c) ON a~b = b~b)

This means that the first join expression is b INNER JOIN c ON b~c = c~c, which joins the columns of tables b and c based on the condition that b~c equals c~c. The second join expression is a INNER JOIN (b INNER JOIN c ON b~c = c~c) ON a~b = b~b, which joins the columns of table a and the result of the first join expression based on the condition that a~b equals b~b. The final result set contains all combinations of rows from tables a, b, and c that satisfy both join conditions.

References: 1: SELECT, FROM JOIN - ABAP Keyword Documentation - SAP Online Help