tRiakInput Standard properties

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.

Use existing connection

Select this check box and in the Component List drop-down list, select the desired 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

Type in the name of the bucket from which you want to read data.

Key

Type in the key which is associated with the data that you want to read.

Output key to column

Select this check box and from the list select the desired column to which the keys will be output.

Values column

Customize the columns to which the values will be output.

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

NB_LINE: the number of rows read by an input component or transferred to an output component. 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 always needs an output link.