Talend-Core-Developer Talend Core Certified Developer Exam Practice Test

Answer : A

To call a different job within a job you are developing, you can use the tRunJob component. This component allows you to execute another job as a subjob within a parent job. To pass the parameters to the job you want to call, you can use the context parameters. Context parameters are variables that can store values that can be changed at runtime or between different contexts. You can define context parameters in the Contexts tab of your job and assign them values for each context. You can also pass context parameters from the parent job to the child job by using the Context Param tab of the tRunJob component. This way, you can parameterize the properties or expressions of the child job with the values from the parent job.

You do not need to use a file, command line options, or Java function parameters to pass parameters to a different job. These methods are not supported by Talend Studio and may cause errors or unexpected results. Reference: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [tRunJob properties - 7.3], [Contexts - 7.3]

Answer : D, E

Trace Debug mode is a feature that allows you to trace each row processed by your job components and see the values of each column in each row. You can access this mode by opening the Debug Run tab of the Run view and clicking on Trace Debug button.

The capabilities that Trace Debug mode provides are:

Breaking when an input column fulfills a condition. You can set breakpoints on traces based on a condition or an expression that involves input data columns. For example, you can set a breakpoint to pause your job when a customer name contains a certain string or when a product price exceeds a certain value. To set a breakpoint based on a condition, you need to right-click on a trace on your job design workspace and select Show Breakpoint Setup option. This will open a dialog box where you can enter a condition or an expression for your breakpoint.

Advancing one row at a time. You can advance the execution of your job one row at a time by using the Step Over button in the toolbar of the Run view. This will allow you to see how each row is processed by your job components and how it affects the output data.

The capabilities that Trace Debug mode does not provide are:

Filtering which data is propagated by a flow. You cannot filter which data is propagated by a flow in Trace Debug mode. A flow is a link that shows the data transfer between components in your job design workspace. In Trace Debug mode, you can see the data flow on each trace and inspect the values of each column for each row processed by your job. However, you cannot change which rows are propagated by a flow based on a condition or an expression.

Advancing one column at a time. You cannot advance the execution of your job one column at a time in Trace Debug mode. You can only advance the execution of your job one row at a time by using the Step Over button in the toolbar of the Run view. This will allow you to see how each row is processed by your job components and how it affects the output data. However, you cannot see how each column is processed by your job components and how it affects the output data.

Breaking on a selected line of code. You cannot break on a selected line of code in Trace Debug mode. You can only break on a trace based on a condition or an expression that involves input data columns. To break on a selected line of code, you need to use Java Debug mode. Java Debug mode allows you to debug your job code in Java or Perl and see the values of each variable or expression in your code. You can access this mode by switching to the Java perspective and clicking on the Debug button in the toolbar of the Code view. Reference: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [Trace Debug mode - 7.3], [Java Debug mode - 7.3]

Answer : A, D

Trace Debug and Java Debug are two modes that allow you to debug your jobs in Talend Studio. Trace Debug mode allows you to trace each row processed by your job components and see the values of each column in each row. Java Debug mode allows you to debug your job code in Java or Perl and see the values of each variable or expression in your code.

The characteristics that distinguish Trace Debug from Java Debug are:

Trace Debug mode allows row-by-row inspection of data flows, while Java Debug mode does not. Data flows are the links that show the data transfer between components in your job design workspace. In Trace Debug mode, you can see the data flow on each trace and inspect the values of each column for each row processed by your job. You can also use filters to display only the rows that match a condition or an expression. In Java Debug mode, you cannot see the data flow on each trace or inspect the values of each column for each row.

Trace Debug mode supports breakpoints based on input data condition, while Java Debug mode does not. Breakpoints are points where the execution of your job pauses and waits for your action. You can use breakpoints to inspect your data or debug your logic at specific points of your job execution. In Trace Debug mode, you can set breakpoints on traces based on a condition or an expression that involves input data columns. For example, you can set a breakpoint to pause your job when a customer name contains a certain string or when a product price exceeds a certain value. In Java Debug mode, you can only set breakpoints on lines of code based on a condition or an expression that involves variables or expressions.

The characteristics that do not distinguish Trace Debug from Java Debug are:

Both modes require a separate perspective. A perspective is a set of views and editors that are arranged in a specific way to support a specific task. In Talend Studio, you can switch between different perspectives, such as Integration, Debug, Profiling, etc. To use Trace Debug mode, you need to switch to the Debug perspective by clicking on the Open Perspective button and selecting Debug. To use Java Debug mode, you need to switch to the Java perspective by clicking on the Open Perspective button and selecting Java.

Neither mode requires Java development experience. Although Java Debug mode allows you to debug your job code in Java or Perl, you do not need to have Java development experience to use it. You can use the graphical interface of Talend Studio to design your job components and properties without writing any code. You can also use the Code view to see the generated code of your job in Java or Perl and modify it if needed. However, you do not need to write any code from scratch or understand all the details of the code to use Java Debug mode. Reference: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [Trace Debug mode - 7.3], [Java Debug mode - 7.3]

Answer : D

To debug a job using Trace Debug mode and pause the execution when it encounters any records for customers residing in the state of California, you need to right-click on the trace on the output of the input component and select Show Breakpoint Setup option. Trace Debug mode is a feature that allows you to trace each row processed by your job components and see the values of each column in each row. You can access this mode by opening the Debug Run tab of the Run view and clicking on Trace Debug button. A trace is a link that shows the data flow between components in your job design workspace.

The Show Breakpoint Setup option allows you to set a breakpoint on a trace based on a condition or an expression. A breakpoint is a point where the execution of your job pauses and waits for your action. You can use breakpoints to inspect your data or debug your logic at specific points of your job execution. You can access this option by right-clicking on a trace on your job design workspace and selecting Show Breakpoint Setup. This will open a dialog box where you can enter a condition or an expression for your breakpoint.

For example, if you want to pause your job execution when it encounters any records for customers residing in the state of California, you can enter this condition for your breakpoint:

row1.state == ''CA''

This will make your job stop at the trace where this condition is met and show you the values of each column for that row.

You do not need to add a breakpoint in Advanced settings tab of Run view, open Debug Run tab of Run view and click Trace Debug button, or right-click on trace on output of input component and select Add Breakpoint option. These options are not used to set breakpoints based on conditions or expressions. The Advanced settings tab of Run view is used to configure advanced settings for your job execution, such as JVM arguments, statistics parameters, implicit context load parameters, etc. The Debug Run tab of Run view is used to access Trace Debug mode, but not to set breakpoints. The Add Breakpoint option is used to add a simple breakpoint on a trace without any condition or expression. Reference: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [Trace Debug mode - 7.3], [Breakpoints - 7.3]

Answer : D

To reuse a job named testJob from a referenced project named project_ref in your main job, you need to navigate to @Referenced project, @project_ref, Job Designs, Standard, then select testJob. A referenced project is a project that can be accessed from another project in read-only mode. You can add a referenced project to your main project by using the Project Settings window in Talend Studio. You can then browse the items (such as jobs, metadata, routines, etc.) of the referenced project in the Repository tree view under the @Referenced project node. You can drag and drop any item from the referenced project to your main job design workspace.

You do not need to use import items, create standard job, or navigate to Metadata options. These options are not used to reuse jobs from referenced projects. The import items option is used to import items (such as jobs, metadata, routines, etc.) from an archive file that can be exported from another project or workspace. The create standard job option is used to create a new job with a name and a description. The Metadata node in the Repository tree view is used to store and manage metadata definitions for various data sources (such as databases, files, web services, etc.). Reference: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [Referenced projects - 7.3]

Answer : C

When you modify the schema of a component in Talend Studio, the application prompts you to propagate these changes. This propagation ensures that any alterations to the data structure are consistently applied throughout the Job, maintaining data integrity and coherence.

Understanding Schema Propagation:

Purpose: Schema propagation is essential to synchronize the data structure across connected components. When a schema changes (e.g., adding or removing a column), downstream components that rely on this schema need to be updated to reflect these changes.

Prompt Significance: The prompt serves as a confirmation to apply the schema changes to the subsequent components in the Job. By agreeing to propagate, Talend Studio automatically updates the schemas of all downstream components connected to the modified component.

Example Scenario:

Consider a Job where a tFileInputDelimited component reads data and passes it to a tMap component, which then outputs to a tFileOutputDelimited component. If you add a new column to the schema of tFileInputDelimited:

Modification:

You add a new column, 'emailAddress', to the tFileInputDelimited schema.

Propagation Prompt:

Upon making this change, Talend Studio prompts you to propagate the schema changes.

Effect of Propagation:

By confirming, the 'emailAddress' column is added to the schemas of all downstream components (e.g., tMap and tFileOutputDelimited). This ensures that these components recognize and can process the new column appropriately.

By understanding and utilizing schema propagation, you ensure that all components within your Talend Jobs remain synchronized, reducing errors and enhancing data processing efficiency.

Answer : C

To create a generic schema from a schema defined in a Talend component, follow these steps:

Open the Repository View:

In Talend Studio, navigate to the Repository panel, typically located on the left side of the interface.

Locate the 'Generic schemas' Node:

Within the Repository, expand the 'Metadata' section to find the 'Generic schemas' node.

Initiate the Generic Schema Creation Process:

Right-click on 'Generic schemas' and select 'Create generic schema' from the context menu.

Define the Schema Properties:

In the schema creation wizard that appears, provide the necessary properties such as 'Name' and 'Description' for the new generic schema.

Set Up the Schema Structure:

Define the schema structure by adding columns and specifying their data types as required.

Finalize the Schema Creation:

Click 'Finish' to complete the creation process. The new generic schema will now be available under the 'Generic schemas' node in the Repository.

This method allows you to create a reusable generic schema that can be applied across multiple components and Jobs within Talend Studio.