Schema and Edit schema

A schema is a row description. It defines the number of fields
(columns) to be processed and passed on to the next component. When you create a Spark
Job, avoid the reserved word line when naming the
fields.

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.

Repository: You have already created the schema and stored it in the
Repository. You can reuse it in various projects and Job designs.

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.

You can find more details about how to
verify default values in retrieved schema in Talend Help Center (https://help.talend.com).

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.

If you select the Use an existing
connection check box, the Nodes table will not be available.

Nodes

Fill in the information required for a connection to a Riak
cluster.

• Host: enter the IP
  address or hostname of a Riak node in the Riak cluster that
  you want to connect to.

• Port: enter the listening
  port number of a Riak node. You can leave this field empty
  to use its default value 8098.

• Riak path: enter the Riak
  path for accessing a Riak node. You can leave this field
  empty to use its defalt value riak.

One example of the URL for accessing a Riak node is http://127.0.0.1:8098/riak.

For more information about the concepts related to Riak, see https://docs.basho.com/riak/kv/2.2.0/learn/concepts/.

Bucket

Specify the name of the bucket to which you want to apply
changes.

Action on data

In the specified bucket, you can perform:

• Upsert: Insert data if
  they do not exist or update the existing data.

• Delete: Remove values
  associated with the specified key.

If you select Delete from the Action on data list, only the Key column list is available in the Key area.

Auto generate the key

Select this check box to let the Riak system generate keys for the
values automatically.

Key column

Select one column from the list to write its data into the Riak
bucket as keys. Note that the key must be unique across one
bucket.

Value columns

Customize the columns to write their data into the Riak bucket as
values.

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

UPSERT_NB_LINE: the number of rows inserted and updated.
This is an After variable and it returns an integer.

DELETE_NB_LINE: the number of rows deleted. This is an
After variable and it returns an integer.

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 rule

This component is used as an output component and it always needs
an incoming link.