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To execute the compiled job outside Talend Studio, you need to right-click on the job in the Repository tree view and select Build Job option. This option allows you to export your job as an executable file that can be run independently from Talend Studio on any platform that supports Java. You can access this option by right-clicking on your job in the Repository tree view and selecting Build Job. This will open a dialog box where you can configure the build settings, such as destination folder, archive name, context, etc.

You do not need to click the Export button in the Edit Properties window, right-click on the job in the Repository and select Export items, or select Save As on the main File menu. These options are not used to execute the compiled job outside Talend Studio. The Export button in the Edit Properties window is used to export your job properties as an XML file. The Export items option is used to export your items (such as jobs, metadata, routines, etc.) as an archive file that can be imported into another project or workspace. The Save As option is used to save a copy of your job with a different name or location. References: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [Build Job - 7.3]

 The tDBInput component allows you to configure the connection properties either by using a built-in mode or by using a repository mode. The built-in mode lets you set all the relevant properties manually, such as host, port, database, username, password, etc. The repository mode lets you reuse an existing connection metadata that is stored in the repository. If you have multiple jobs that use different credentials to connect to a common database server, you should use the built-in mode and set the properties for each job individually. This way, you can avoid creating multiple connection metadata in the repository and maintain them separately. References: Talend Data Integration — Software to Connect, Access, and Transform Data | Talend, [tDBInput properties - 7.3]

The tMap component allows you to configure different types of joins between the main input and the lookup tables, such as inner join, left outer join, right outer join, etc. An inner join returns only the matching rows from both tables based on a join condition. If a row from the main input does not match any row from the lookup table, it is considered as an inner join reject. You can configure an output to collect these rejects by setting the Catch inner join reject option to true. The name of the output row that delivers the join rejects is determined by the output table you create to catch the rejects. You can name the output table as you wish, such as Rejects, Errors, etc. References: Talend Open Studio: Open-source ETL and Free Data Integration | Talend,

To create a centralized metadata connection to a database server for an application, you need to take the following steps before building a job that reads from that database:

Create DB Connections metadata to describe the database connection. You can do this by right-clicking on the DB Connections node in the Repository and selecting Create Connection. You can then enter the connection details, such as host, port, database, username, password, etc., and test the connection.

Retrieve schemas from the database connection. You can do this by expanding the DB Connections node in the Repository and right-clicking on the connection you created. You can then select Retrieve Schema and choose the tables or views you want to import as metadata schemas. You can also edit or customize the schemas as needed.

Drag the DB Connection metadata into the Designer to read from the database component. You can do this by dragging the connection or a specific schema from the Repository to the Designer workspace. This will automatically create a database input component (such as tMysqlInput) that is configured with the connection and schema properties. You can then use this component to read data from the database in your job.

You do not need to add a tMap component to handle and convert DB Types, nor a tCreateTable component to create a table in the database. These components are not required for reading data from an existing database, but they can be used for other purposes, such as transforming or writing data. References: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [DB Connections - 7.3], [tMap properties - 7.3], [tCreateTable properties - 7.3]

You need to use the following code in a tJava component to write a nb_line variable:

int nb_line = (Integer)globalMap.get(“tFileInputDelimited_1_NB_LINE”);

This code retrieves the value of the global variable tFileInputDelimited_1_NB_LINE, which stores the number of rows processed by the tFileInputDelimited component, and assigns it to an integer variable named nb_line. You can then use this variable to print or manipulate the number of rows in your Job. Note that you need to use globalMap.get, not globalMap.put, to access the value of a global variable.

The generic Input component used for in a Joblet design is the tJobletInput component. This component is used to carry data into a Joblet from another component in the job that contains the Joblet. A Joblet is a reusable piece of a job that can be used in multiple jobs as a single component. A Joblet can have one or more input and output flows that connect it with other components in a job. To create these flows, you need to use generic input and output components, such as tJobletInput, tJobletOutput, tJobletTriggerInput, and tJobletTriggerOutput. These components allow you to define schemas and triggers for your Joblet without depending on specific components.

The tJobletInput component is not used for triggering a Joblet, triggering a subjob, or carrying data into a subjob. These are different concepts and functionalities in Talend Studio. A trigger is a link that activates a subjob or a component based on a condition or an event. A subjob is a part of a job that consists of one or more components connected by data flows or triggers. A subjob can be triggered by another subjob using triggers such as OnSubjobOk, OnSubjobError, Run if, etc. A subjob can also carry data into another subjob using data flows such as main, lookup, reject, etc. References: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [tJobletInput properties - 7.3], [Joblets - 7.3], [Triggers - 7.3]

A Joblet is a reusable piece of a job that can be used in multiple jobs as a single component. A tRunJob component is a component that allows you to call another job as a subjob within a parent job. When comparing a Joblet to a tRunJob component, these statements are true:

A Joblet uses the same context variables of the job in which it is used, unlike a tRunJob component. A context variable is a variable that can store a value that can be changed at runtime or between different contexts. A Joblet inherits the context variables from the job that contains it and does not have its own context variables. A tRunJob component can pass context variables from the parent job to the child job, or use a specific context for the child job.

Building a Joblet typically requires the use of generic input and trigger components. A Joblet can have one or more input and output flows that connect it with other components in a job. To create these flows, you need to use generic input and trigger components, such as tJobletInput, tJobletOutput, tJobletTriggerInput, and tJobletTriggerOutput. These components allow you to define schemas and triggers for your Joblet without depending on specific components.

The nested job called by a tRunJob component cannot use the same context variables of the job in which it is used. A nested job is a job that is called by another job using a tRunJob component. A nested job can have its own context variables or receive context variables from its parent job, but it cannot use thesame context variables as its parent job. This means that if you have two context variables with the same name in both jobs, they will be treated as separate variables and will not share values.

These statements are false when comparing a Joblet to a tRunJob component:

The performance of tRunJob component is better than running an equivalent job using a Joblet. The performance of a Joblet is better than running an equivalent job using a tRunJob component. This is because a Joblet is integrated into the main code of the job and does not require launching another JVM process or loading another metadata object like a tRunJob component does. References: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [Joblets - 7.3], [tRunJob properties - 7.3], [Contexts - 7.3]

The Start component in a subjob triggers the execution of the next subjob in a sequential order. The Start component is used to define where a subjob begins and to link it with other subjobs within a job. The Start component has only one output link that can be connected to any other component in the same subjob or to another Start component in another subjob. When a subjob completes successfully, it sends an OnSubjobOk trigger to its Start component, which then activates the next subjob linked to it. The Final component, on the other hand, is used to define where a subjob ends and to perform some actions after its completion, such as sending anemail or logging a message. The Final component has no output link and does not trigger any other subjob. The Input component and any other component in a subjob do not trigger any other subjob by themselves, unless they are connected to a Start component through an output link or an OnComponentOk trigger. References: Talend Open Studio: Open-source ETL and Free Data Integration | Talend, [Start properties - 7.3], [Final properties - 7.3]

Contexts are a way of defining different sets of values for variables that are used in a job. For example, you can define a context for testing and another context for production, with different values for the database connection parameters, file paths, etc. You can then switch between the contexts easily without modifying the job design. Contexts are not automatically defined by the types of components used in the job, nor by Talend Studio. You must define the contexts yourself in the Contexts tab of your job. You can also create context groups in the Repository and reuse them in multiple jobs. References: Talend Data Integration — Software to Connect, Access, and Transform Data | Talend,

The tMap component allows you to set up a filter on the input fields by using the Expression filter in the output table. The Expression filter is a field where you can enter a logical expression that evaluates to true or false for each input row. For example, if you want to filter out the rows that have null values in a certain column, you can use row1.column != null as the expression filter for that output. The expression filter applies to all the input fields of the row, not just a single column. You cannot set up a filter on the input fields by using the Match Model parameter field for one of the inputs or outputs, as this field is used to define how to match rows between different inputs or outputs based on a key attribute. References: Talend Open Studio: Open-source ETL and Free Data Integration | Talend