tSqoopMerge Standard properties

Sqoop

author
Talend Documentation Team
EnrichVersion
6.4
EnrichProdName
Talend Real-Time Big Data Platform
Talend Data Fabric
Talend Big Data Platform
Talend Big Data
Talend Open Studio for Big Data
task
Design and Development > Third-party systems > Database tools > Sqoop components
Data Governance > Third-party systems > Database tools > Sqoop components
Data Quality and Preparation > Third-party systems > Database tools > Sqoop components
EnrichPlatform
Talend Studio

These properties are used to configure tSqoopMerge running in the Standard Job framework.

The Standard tSqoopMerge component belongs to the Big Data and the File families.

The component in this framework is available when you are using one of the Talend solutions with Big Data.

Basic settings

Mode

Select the mode in which Sqoop is called in a Job execution.

Use Commandline: the Sqoop shell is used to call Sqoop. In this mode, you have to deploy and run the Job in the host where Sqoop is installed. Therefore, if you are a subscription-based user, we recommend installing and using a Jobserver provided by Talend in that host to run the Job; if you are using one of the Talend solutions with Big Data, you have to ensure that the Studio and the Sqoop to be used are in the same machine.

Use Java API: the Java API is used to call Sqoop. In this mode, the Job can be run locally in the Studio but you need to configure the connection to the Hadoop distribution to be used. Note that JDK is required to execute the Job in the Java API mode and the versions of the JDK kits installed in both machines must be compatible with each other; for example, the versions are the same or the JDK version of the Hadoop machine is more recent.

Hadoop properties

Either Built-in or Repository:
  • Built-in: you enter the configuration information of the Hadoop distribution to be used locally for this component only.

  • Repository: you have already created the Hadoop connection and stored it in the Repository; therefore, you reuse it directly for the component configuration and the Job design. For further information about how to create a centralized Hadoop connection, see Talend Open Studio for Big Data Getting Started Guide .

Distribution

Select the cluster you are using from the drop-down list. The options in the list vary depending on the component you are using. Among these options, the following ones requires specific configuration:
  • If available in this Distribution drop-down list, the Microsoft HD Insight option allows you to use a Microsoft HD Insight cluster. For this purpose, you need to configure the connections to the WebHCat service, the HD Insight service and the Windows Azure Storage service of that cluster in the areas that are displayed. A demonstration video about how to configure this connection is available in the following link: https://www.youtube.com/watch?v=A3QTT6VsNoM.

  • If you select Amazon EMR, see the following article about how to configure the connection: Amazon EMR - Getting Started.

  • The Custom option allows you to connect to a cluster different from any of the distributions given in this list, that is to say, to connect to a cluster not officially supported by Talend .

  1. Select Import from existing version to import an officially supported distribution as base and then add other required jar files which the base distribution does not provide.

  2. Select Import from zip to import the configuration zip for the custom distribution to be used. This zip file should contain the libraries of the different Hadoop elements and the index file of these libraries.

    In Talend Exchange, members of Talend community have shared some ready-for-use configuration zip files which you can download from this Hadoop configuration list and directly use them in your connection accordingly. However, because of the ongoing evolution of the different Hadoop-related projects, you might not be able to find the configuration zip corresponding to your distribution from this list; then it is recommended to use the Import from existing version option to take an existing distribution as base to add the jars required by your distribution.

    Note that custom versions are not officially supported by Talend . Talend and its community provide you with the opportunity to connect to custom versions from the Studio but cannot guarantee that the configuration of whichever version you choose will be easy, due to the wide range of different Hadoop distributions and versions that are available. As such, you should only attempt to set up such a connection if you have sufficient Hadoop experience to handle any issues on your own.

    Note:

    In this dialog box, the active check box must be kept selected so as to import the jar files pertinent to the connection to be created between the custom distribution and this component.

    For a step-by-step example about how to connect to a custom distribution and share this connection, see Connecting to a custom Hadoop distribution.

Hadoop Version

Select the version of the Hadoop distribution you are using. The available options vary depending on the component you are using. Along with the evolution of Hadoop, please note the following changes:
  • If you use Hortonworks Data Platform V2.2, the configuration files of your cluster might be using environment variables such as ${hdp.version}. If this is your situation, you need to set the mapreduce.application.framework.path property in the Hadoop properties table of this component with the path value explicitly pointing to the MapReduce framework archive of your cluster. For example:
    mapreduce.application.framework.path=/hdp/apps/2.2.0.0-2041/mapreduce/mapreduce.tar.gz#mr-framework
  • If you use Hortonworks Data Platform V2.0.0, the type of the operating system for running the distribution and a Talend Job must be the same, such as Windows or Linux. Otherwise, you have to use Talend Jobserver to execute the Job in the same type of operating system in which the Hortonworks Data Platform V2.0.0 distribution you are using is run.

NameNode URI

Type in the URI of the Hadoop NameNode, the master node of a Hadoop system. For example, we assume that you have chosen a machine called masternode as the NameNode, then the location is hdfs://masternode:portnumber. If you are using WebHDFS, the location should be webhdfs://masternode:portnumber; if this WebHDFS is secured with SSL, the scheme should be swebhdfs and you need to use a tLibraryLoad in the Job to load the library required by the secured WebHDFS.

JobTracker Host

Select this check box and in the displayed field, enter the location of the ResourceManager of your distribution. For example, tal-qa114.talend.lan:8050.

This property is required when the query you want to use is executed in Windows and it is a Select query. For example, SELECT your_column_name FROM your_table_name

Then you can continue to set the following parameters depending on the configuration of the Hadoop cluster to be used (if you leave the check box of a parameter clear, then at runtime, the configuration about this parameter in the Hadoop cluster to be used will be ignored ):
  1. Select the Set resourcemanager scheduler address check box and enter the Scheduler address in the field that appears.

  2. Select the Set jobhistory address check box and enter the location of the JobHistory server of the Hadoop cluster to be used. This allows the metrics information of the current Job to be stored in that JobHistory server.

  3. Select the Set staging directory check box and enter this directory defined in your Hadoop cluster for temporary files created by running programs. Typically, this directory can be found under the yarn.app.mapreduce.am.staging-dir property in the configuration files such as yarn-site.xml or mapred-site.xml of your distribution.

  4. Allocate proper memory volumes to the Map and the Reduce computations and the ApplicationMaster of YARN by selecting the Set memory check box in the Advanced settings view.

  5. Select the Set Hadoop user check box and enter the user name under which you want to execute the Job. Since a file or a directory in Hadoop has its specific owner with appropriate read or write rights, this field allows you to execute the Job directly under the user name that has the appropriate rights to access the file or directory to be processed.

  6. Select the Use datanode hostname check box to allow the Job to access datanodes via their hostnames. This actually sets the dfs.client.use.datanode.hostname property to true. When connecting to a S3N filesystem, you must select this check box.

For further information about these parameters, see the documentation or contact the administrator of the Hadoop cluster to be used.

For further information about the Hadoop Map/Reduce framework, see the Map/Reduce tutorial in Apache's Hadoop documentation on http://hadoop.apache.org.

Use kerberos authentication

If you are accessing the Hadoop cluster running with Kerberos security, select this check box, then, enter the Kerberos principal name for the NameNode in the field displayed. This enables you to use your user name to authenticate against the credentials stored in Kerberos.
  • If this cluster is a MapR cluster of the version 4.0.1 or later, you can set the MapR ticket authentication configuration in addition or as an alternative by following the explanation in Connecting to a security-enabled MapR.

    Keep in mind that this configuration generates a new MapR security ticket for the username defined in the Job in each execution. If you need to reuse an existing ticket issued for the same username, leave both the Force MapR ticket authentication check box and the Use Kerberos authentication check box clear, and then MapR should be able to automatically find that ticket on the fly.

In addition, since this component performs Map/Reduce computations, you also need to authenticate the related services such as the Job history server and the Resource manager or Jobtracker depending on your distribution in the corresponding field. These principals can be found in the configuration files of your distribution. For example, in a CDH4 distribution, the Resource manager principal is set in the yarn-site.xml file and the Job history principal in the mapred-site.xml file.

This check box is available depending on the Hadoop distribution you are connecting to.

Use a keytab to authenticate

Select the Use a keytab to authenticate check box to log into a Kerberos-enabled Hadoop system using a given keytab file. A keytab file contains pairs of Kerberos principals and encrypted keys. You need to enter the principal to be used in the Principal field and the access path to the keytab file itself in the Keytab field.

Note that the user that executes a keytab-enabled Job is not necessarily the one a principal designates but must have the right to read the keytab file being used. For example, the user name you are using to execute a Job is user1 and the principal to be used is guest; in this situation, ensure that user1 has the right to read the keytab file to be used.

Hadoop user name

Enter the user name under which you want to execute the Job. Since a file or a directory in Hadoop has its specific owner with appropriate read or write rights, this field allows you to execute the Job directly under the user name that has the appropriate rights to access the file or directory to be processed. Note that this field is available depending on the distribution you are using.

Old data directory

Enter the path to the older dataset to be merged.

New data directory

Enter the path to the newer dataset to be merged.

Target directory

Enter the directory where you need to put the output of the merging.

Merge key

Enter the name of the column used as the key of each record for the merging.

This primary key must be unique.

Need to generate the JAR file

Select this check box to generate the merge jar file and the merge class required to parse the datasets to be merged. The default name of the jar file and the class is SqoopMerge_component_ID. This compnent_ID is the ID of the tSqoopMerge component that generates the jar file and the class, such as tSqoopMerge_1, or tSqoopMerge_2.

As this jar file is generated from the source table of the imported data, selecting this check box displays the corresponding parameters to be set for connecting to that table.

JDBC property

Either Built-in or Repository:
  • Built-in: you enter the connection information of the database to be used locally for this component only.

  • Repository: you have already created the database connection and stored it in the Repository; therefore, you reuse it directly for the component configuration and the Job design. For further information about how to create a centralized database connection, see Talend Studio User Guide.

    Note that only the General JDBC connection stored in the Repository is supported.

Connection

Enter the JDBC URL used to connect to the database where the source data is stored.

User name and Password

Enter the authentication information used to connect to the source database.

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.

Table Name

Type in the name of the source table.

This name is used to name the generated jar file.

Driver JAR

In either the Use Commandline mode or the Java API mode, you must add the driver file of the database to be used to the lib folder of the Hadoop distribution you are using. For that purpose, use this Driver JAR table to add that driver file for the current Job you are designing.

This driver jar is required only when you need to connect to the database to be used to generate the merge jar file; therefore this Driver JAR table is available only when you have selected the Need to generate the JAR file check box.

JAR file

If a required merge class already exists and is available, specify the access path to the jar file that contains that class for reusing the class.

In this situation, you need to enter the name of the class in the Class name field in the Advanced settings tab.

Print Log

Select this check box to activate the Verbose check box.

Verbose

Select this check box to print more information while working, for example, the debugging information.

Advanced settings

Custom class name

Select this check box to display the Class name field and enter the name of the merge class you need to use.

This check box must be clear if you use Generate the JAR file in the Basic settings tab.

Additional arguments

Complete this table to use additional arguments if needs be.

By adding additional arguments, you are able to perform multiple operations in one single transaction. For example, you can use --hive-import and --hive-table in the Commandline mode or hive.import and hive.table.name in the Java API mode to create Hive table and write data in at the runtime of the transaction writing data in HDFS. For further information about the available Sqoop arguments in the Commandline mode and the Java API mode, respectively, see Additional arguments.

Hadoop properties

Talend Studio uses a default configuration for its engine to perform operations in a Hadoop distribution. If you need to use a custom configuration in a specific situation, complete this table with the property or properties to be customized. Then at runtime, the customized property or properties will override those default ones.
  • Note that if you are using the centrally stored metadata from the Repository, this table automatically inherits the properties defined in that metadata and becomes uneditable unless you change the Property type from Repository to Built-in.

For further information about the properties required by Hadoop and its related systems such as HDFS and Hive, see the documentation of the Hadoop distribution you are using or see Apache's Hadoop documentation on http://hadoop.apache.org/docs and then select the version of the documentation you want. For demonstration purposes, the links to some properties are listed below:

Mapred job map memory mb and Mapred job reduce memory mb

If the Hadoop distribution to be used is Hortonworks Data Platform V1.2 or Hortonworks Data Platform V1.3, you need to set proper memory allocations for the map and reduce computations to be performed by the Hadoop system.

In that situation, you need to enter the values you need in the Mapred job map memory mb and the Mapred job reduce memory mb fields, respectively. By default, the values are both 1000 which are normally appropriate for running the computations.

If the distribution is YARN, then the memory parameters to be set become Map (in Mb), Reduce (in Mb) and ApplicationMaster (in Mb), accordingly. These fields allow you to dynamically allocate memory to the map and the reduce computations and the ApplicationMaster of YARN.

Path separator in server

Leave the default value of the Path separator in server as it is, unless you have changed the separator used by your Hadoop distribution's host machine for its PATH variable or in other words, that separator is not a colon (:). In that situation, you must change this value to the one you are using in that host.

tStatCatcher Statistics

Select this check box to collect log data at the component level.

Global Variables

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.

EXIT_CODE: the exit code of the remote command. This is an After variable and it returns an integer.

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

Usage rule

This component is used standalone. It respects the Sqoop prerequisites. You need necessary knowledge about Sqoop to use it.

We recommend using the Sqoop of version 1.4+ in order to benefit the full functions of these components.

For further information about Sqoop, see the Sqoop manual on: http://sqoop.apache.org/docs/

Prerequisites

The Hadoop distribution must be properly installed, so as to guarantee the interaction with Talend Studio . The following list presents MapR related information for example.

  • Ensure that you have installed the MapR client in the machine where the Studio is, and added the MapR client library to the PATH variable of that machine. According to MapR's documentation, the library or libraries of a MapR client corresponding to each OS version can be found under MAPR_INSTALL\ hadoop\hadoop-VERSION\lib\native. For example, the library for Windows is \lib\native\MapRClient.dll in the MapR client jar file. For further information, see the following link from MapR: http://www.mapr.com/blog/basic-notes-on-configuring-eclipse-as-a-hadoop-development-environment-for-mapr.

    Without adding the specified library or libraries, you may encounter the following error: no MapRClient in java.library.path.

  • Set the -Djava.library.path argument, for example, in the Job Run VM arguments area of the Run/Debug view in the [Preferences] dialog box in the Window menu. This argument provides to the Studio the path to the native library of that MapR client. This allows the subscription-based users to make full use of the Data viewer to view locally in the Studio the data stored in MapR.

For further information about how to install a Hadoop distribution, see the manuals corresponding to the Hadoop distribution you are using.

Limitation

If you have selected the Use Commandline mode, you need to use the host where Sqoop is installed to run the Job using this component.

Connections

Outgoing links (from this component to another):

Trigger: Run if; On Subjob Ok; On Subjob Error; On Component Ok; On Component Error.

Incoming links (from one component to this one):

Row: Iterate;

Trigger: Run if; On Subjob Ok; On Subjob Error; On Component Ok; On Component Error

For further information regarding connections, see Talend Studio User Guide.