tMongoDBRow

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This component will be available in the Palette of
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solutions with Big Data.

tMongoDBRow Properties

Component family	Big Data / MongoDB
Function	tMongoDBRow executes the commands and functions provided by the MongoDB database.
Purpose	This component allows you to execute the commands and functions of the MongoDB database.
Basic settings	Use existing connection	Select this check box and in the Component List click the relevant connection component to reuse the connection details you already defined.
	DB Version	List of the database versions. Available when the Use existing connection check box is not selected.
	Use replica set address	Select this check box to show the Replica address table. In the Replica address table, you can define multiple MongoDB database servers for failover. Available when the Use existing connection check box is not selected.
	Server and Port	Address and listening port of the database server. Available when the Use existing connection or Use replica set address check box is not selected.
	Database	Name of the database.
	Use SSL connection	Select this check box to enable the SSL encrypted connection. Then you need to use the tSetKeystore component in the same Job to specify the authentication information. For further information about tSetKeystore, see tSetKeystore. Note that the SSL connection is available only for the version 2.4 + of MongoDB.
	Required authentication	Select this check box to enable the database authentication.
	Username and Password	DB user authentication data. To enter the password, click the […] button next to the password field, and then in the pop-up dialog box enter the password between double quotes and click OK to save the settings. Available when the Required authentication check box is selected.
	Schema and Edit Schema	A schema is a row description. It defines the number of fields to be processed and passed on to the next component. The schema is either Built-In or stored remotely in the Repository. Click Edit schema to make changes to the schema. If the current schema is of the Repository type, three options are available: View schema: choose this option to view the schema only. Change to built-in property: choose this option to change the schema to Built-in for local changes. Update repository connection: choose this option to change the schema stored in the repository and decide whether to propagate the changes to all the Jobs upon completion. If you just want to propagate the changes to the current Job, you can select No upon completion and choose this schema metadata again in the [Repository Content] window. Click Sync columns to retrieve the schema from the previous component connected in the Job.
	Execute command	Select this check box to enter MongoDB commands in the Command field for execution.
	Function	Enter MongoDB functions in the Function field for execution. Not available when the Execute command check box is selected.
	Parameters value	Click the [+] button to add lines as needed and then define the parameter values in the form of variables or constant values, for example row1.author or “Andy”. Note that the parameter values correspond to the parameters defined in the Function field, in the same order. Not available when the Execute command check box is selected.
	Die on error	This check box is cleared by default, meaning to skip the row on error and to complete the process for error-free rows.
Advanced settings	tStatCatcher Statistics	Select this check box to collect the log data at the component level.
Global Variables	ERROR_MESSAGE: the error message generated by the component when an error occurs. This is an After variable and it returns a string. This variable functions only if the Die on error check box is cleared, if the component has this check box. A Flow variable functions during the execution of a component while an After variable functions after the execution of the component. To fill up a field or expression with a variable, press Ctrl + Space to access the variable list and choose the variable to use from it. For further information about variables, see Talend Studio User Guide.
Usage	tMongoDBRow allows you to manipulate the MongoDB database through the MongoDB commands and functions.
Log4j	The activity of this component can be logged using the log4j feature. For more information on this feature, see Talend Studio User Guide. For more information on the log4j logging levels, see the Apache documentation at http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Level.html.
Limitation	n/a

Scenario: Using MongoDB functions to create a collection and write data to it

This scenario creates the collection blog and writes post
data to it through the MongoDB functions.

Linking the components

Drop tMongoDBConnection, tFixedFlowInput, tMongoDBRow, tMongoDBClose,
tMongoDBInput and tLogRow onto the workspace.
Rename tFixedFlowInput as blog_post_data, tMongoDBRow as write_data_to_collection, tMongoDBInput as read_data_from_collection and tLogRow as show_data_from_collection.
Link tMongoDBConnection to tFixedFlowInput using the OnSubjobOk trigger.
Link tFixedFlowInput to tMongoDBRow using a Row > Main
connection.
Link tFixedFlowInput to tMongoDBInput using the OnSubjobOk trigger.
Link tMongoDBInput to tMongoDBClose using the OnSubjobOk trigger.
Link tMongoDBInput to tLogRow using a Row > Main
connection.

Configuring the components

Double-click tMongoDBConnection to open
its Basic settings view.
From the DB Version list, select the
MongoDB version you are using.
In the Server and Port fields, enter the connection details.

In the Database field, enter the name of the MongoDB
database.

Double-click tFixedFlowInput to open its
Basic settings view.

Select Use Inline Content (delimited
file) in the Mode
area.

In the Content field, enter the data to write to the
MongoDB database, for example:

Andy;Open Source Outlook;Open Source,Talend;Talend, the leader of the open source world...
Andy;Data Integration Overview;Data Integration,Talend;Talend, the leading player in the DI field...
Andy;ELT Overview;ELT,Talend;Talend, the big name in the ELT circle...

Andy;Open Source Outlook;Open Source,Talend;Talend, the leader of the open source world...

Andy;Data Integration Overview;Data Integration,Talend;Talend, the leading player in the DI field...

Andy;ELT Overview;ELT,Talend;Talend, the big name in the ELT circle...

Double-click tMongoDBRow to open its
Basic settings view.

Select the Use existing connection check
box.

In the Function field, enter the MongoDB function to
create the collection blog and insert
data to it:

"function(author,title,keywords,contents){ return db.blog.save( {author:author,title:title,keywords:keywords,contents:contents} ); }"

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"function(author,title,keywords,contents){
return db.blog.save(
{author:author,title:title,keywords:keywords,contents:contents}
);

}"
Click the […] button next to Edit schema to open the schema editor.
Click the [+] button to add four columns
in the right part, namely author,
title, keywords and contents,
with the type of String.

Click to copy all the columns to the input table.

Click OK to close the editor.
In the Parameters value table, click the
[+] button to add four lines and enter
the values in sequence: row1.author,
row1.title, row1.keywords and row1.contents. By doing so, data of row1 will be transferred to the parameters defined in the
function.
Double-click tMongoDBInput to open its
Basic settings view.

Select the Use existing connection check
box.

In the Collection field, enter the name
of the collection, namely blog.
Click the […] button next to Edit schema to open the schema editor.
Click the [+] button to add four columns,
namely author, title, keywords and
contents, with the type as String.

Click OK to close the editor.
Double-click tLogRow to open its
Basic settings view.

In the Mode area, select Table (print values in cells of a table for
better display.