August 17, 2023

tCassandraOutputBulk – Docs for ESB 5.x

tCassandraOutputBulk

tcassandraoutputbulk_icon32_white.png

Warning

This component will be available in the Palette of the studio on the condition that you have subscribed to
one of the Talend solutions with Big
Data.

The tCassandraOutputBulk and tCassandraBulkExec components are generally used together as parts of a two
step process. In the first step, an SSTable is generated. In the second step, this SSTable
is written into Cassandra. These two steps are fused together in the tCassandraOutputBulkExec component, detailed in a separate section. The
advantage of using two separate components is that the data can be transformed before it is
loaded into Cassandra.

tCassandraOutputBulk properties

Component family

Big Data / Cassandra

 

Function

tCassandraOutputBulk receives
data from the preceding component, and creates an SSTable
locally.

Purpose

tCassandraOutputBulk allows you
to prepare an SSTable of large size and process it according to your
needs before loading this SSTable into a column family of a
Cassandra keyspace.

Basic settings

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.

Since version 5.6, both the Built-In mode and the Repository mode are
available in any of the Talend solutions.

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.

 

 

Built-In: You create and store the schema locally for this
component only. Related topic: see Talend Studio
User Guide.

 

 

Repository: You have already created the schema and
stored it in the Repository. You can reuse it in various projects and Job designs. Related
topic: see Talend Studio User Guide.

When the schema to be reused has default values that are integers or functions, ensure that
these default values are not enclosed within quotation marks. If they are, you must remove
the quotation marks manually.

For more details, see https://help.talend.com/display/KB/Verifying+default+values+in+a+retrieved+schema.

 

DB Version

Select the Cassandra version you are using.

 

Keyspace

Type in the name of the keyspace into which you want to write the
SSTable.

 

Column family

Type in the name of the column family into which you want to write
the SSTable.

 

Partitioner

Select the partitioner which determines how data is distributed
across the Cassandra cluster.

  • Random: default
    partitioner in Cassandra 1.1 and earlier.

  • Murmur3: default
    partitioner in Cassandra 1.2.

  • Order preserving: not
    recommended because it assumes keys are UTF8 strings.

For more information about the partitioner, see http://wiki.apache.org/cassandra/Partitioners.

 

Column name comparator

Select the data type for the column names, which is used to sort
columns.

For more information about the comparators, see http://www.datastax.com/docs/1.1/ddl/column_family#about-data-types-comparators-and-validators.

 

SSTable directory

Specify the local directory for the SSTable. Note that the
complete path to the SSTable will be the local directory appended by
the specified keyspace name and column family name.

For example, if you set the local directory to /home/talend/sstable, and specify
testk as the keyspace name
and testc as the column family
name, the complete path to the SSTable will be /home/talend/sstable/testk/testc/.

 

Buffer size

Specify what size the SSTable must reach before it is written into
Cassandra.

Advanced settings

tStatCatcher Statistics

Select this check box to gather the Job processing metadata at the
Job level as well as at each 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

This component always needs an incoming link.

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

Related scenario

No scenario is available for this component yet.


Document get from Talend https://help.talend.com
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