Oracle Cloud Infrastructure Documentation

Using Parameters in Pipelines

In Data Integration, parameters in pipelines originate from parameters that are assigned in data flows and tasks.

For data flow operators that use expressions in the configuration, the values of any parameters that are used in the expressions are also available for reconfiguring in a pipeline.

See Using Data Flow Parameters and About Expression Parameters to learn how to use parameters and expression parameters (also known as scalar parameters) in data flows.

Parameters and expression parameters that are used in data flows and tasks have types and default values. If you don't change the incoming parameter values for tasks and associated data flows in a pipeline, the original default values are used at pipeline design time, or at runtime when you run the pipeline.

The supported incoming parameter data types are:

  • NUMERIC
  • VARCHAR
  • DATE
  • DATETIME
  • DECIMAL
  • DOUBLE
  • FLOAT
  • INTEGER
  • TIMESTAMP
  • TINYINT
  • BOOLEAN
  • LONG
  • STRING

Parameters for the source and target resources in a data loader task can also be reconfigured when the task is used in a pipeline. To learn how to use parameters in data loader tasks, see Using Parameters for Source and Target.

Ways to Reconfigure Parameters in a Pipeline

When you add a parameterized task to a pipeline, you can use the Configuration tab in the Properties panel to reconfigure any of the parameter values specified in that task, or in the associated data flow that an integration task wraps.

To reconfigure an incoming parameter value for a task in a pipeline, you can assign to the input:

  • A specific value directly
  • The value of an output from a previous operator. For example, an output parameter.
  • A user-defined parameter, which lets you set the value at pipeline runtime, or at design time when you create a pipeline task that wraps the pipeline.
  • A system parameter

When you create a pipeline task for a parameterized pipeline, you can use the Configure Parameters page to change the default values of user-defined parameters, if any.

Types of Pipeline Parameters

In Data Integration, the types of parameters you can use in pipelines are user-defined or system-generated.

System-generated parameters can be classified into the following types:

User-defined parameters

User-defined parameters are custom parameters that you create in pipelines to assign to the inputs of incoming parameters for task operators. A user-defined parameter is local to the pipeline where you created it, so you can't reuse a user-defined parameter across pipelines.

A user-defined parameter has a name, a type, and a value. You provide a name and a value when you create a user-defined parameter. The type depends on the type of the incoming parameter that you're assigning the user-defined parameter to. You can't change the type of a user-defined parameter.

The user-defined parameter types that you can create in a pipeline include:

  • Data asset
  • Connection
  • Schema
  • Data entity
  • Condition (from a parameterized join or filter condition)
  • Expression

You can also add parameters of data types such as NUMERIC, VARCHAR, DATE, DECIMAL, and STRING.

While designing a pipeline, you can use the Parameters panel or the Parameters tab on the Properties panel of the pipeline to see the user-defined parameters that have been added.

The user-defined parameters are also available in the Expression Builder when you define an expression in the pipeline using an expression operator.

System parameters

Data Integration generates system parameters that you can use to assign to the inputs of incoming parameters for task operators at runtime. A system parameter has a name and type. You can bind the value of a system parameter to an incoming parameter of the same type but you can't change the value.

The following table shows the system parameters that you can use in a pipeline.

NameTypeDescription
SYS.TASK_START_TIMETIMESTAMPTask start time in UTC.
SYS.TASK_RUN_KEY

STRING

Task run key of the task run.
SYS.TASK_RUN_NAME

STRING

 Task run name of the task run.
SYS.TASK_KEY

STRING

 Key of the task.
SYS.TASK_NAME

STRING

 Name of the task.
SYS.PARENT_TASK_RUN_KEY

STRING

Parent task run key.
SYS.TASK_SCHEDULE_TRIGGER_TIMETIMESTAMPThe trigger time for the schedule (for a task run that's initiated from a schedule). The scheduled time might be different from the task start time.
SYS.TASK_SCHEDULE_TIMEZONESTRINGThe time zone corresponding to the scheduled time, which represents the time zone time as defined in the task schedule.
SYS.RETRY_ATTEMPTINTEGERThe number of run attempts of a task that's configured for retries when a run fails.
SYS.PIPELINE_NAMESTRINGName of the pipeline.
SYS.PIPELINE_IDENTIFIERSTRINGIdentifier of the pipeline.
SYS.TIMEOUTINTEGERThe timeout value (in minutes) of the pipeline. The pipeline run fails when the timeout value is reached.
SYS.WORKSPACE_ID STRING Identifier of the workspace.
SYS.APPLICATION_KEY STRING Key of the application.
SYS.REGION STRING Region name.

While designing a pipeline, you can use the Parameters tab on the Properties panel of the pipeline to see the system pipeline parameters that are available. The Used in column indicates where a parameter is used in the pipeline.

While adding an expression to an expression operator in a pipeline, you can use the Parameters tab in the Expression Builder to see the list of system parameters. You can use system parameters in expressions to log system information.

Output parameters

Output parameters are system-generated parameters for operators that you can use to pass output values from one operator in a pipeline to another operator downstream.

The following table shows some output parameters that you can use.

NameTypeDescription
SYS.STATUSSTRINGStatus of operation (for example, task run)
SYS.ERROR_MESSAGESTRINGError message for operation
SYS.NO_OF_INSERTSINTEGERNumber of rows inserted and updated
SYS.DATA_READINTEGERAmount of data read
SYS.DATA_WRITTENINTEGERAmount of data written
SYS.DURATIONINTEGERDuration of operation
SYS.START_TIME_TIMESTAMPTIMESTAMPStart time of the task execution in Timestamp format.
SYS.END_TIME_TIMESTAMPTIMESTAMPEnd time of the task execution in Timestamp format.
SYS.TASK_RUN_KEY

STRING

 Task run key of the task run.
SYS.TASK_RUN_NAME

STRING

 Task run name of the task run.
SYS.TASK_NAME

STRING

 Name of the task.
SYS.TASK_KEY

STRING

 Key of the task.

While designing a pipeline, you can use the Output tab on the Properties panel of a task operator to view the outputs that can be used as inputs for the next operator.

Note the following:

  • For a SQL task operator associated with a stored procedure, the outputs include any output parameters from the SQL stored procedure.

  • For a merge operator, the outputs available are a combination of output parameters from the system, and the outputs for each operator that's connected to the merge operator.

    • Only the following outputs from the system are available: SYS.STATUS, SYS.START_TIME_TIMESTAMP, and SYS.END_TIME_TIMESTAMP
    • Task outputs are qualified by a task operator name. For example: TASK_OPERATOR_1.SYS.STATUS, TASK_OPERATOR_2.SYS.STATUS
    • Outputs from an expression operator are qualified by the expression operator name and expression identifier. For example: EXPRESSION_1.EXPRESSION_ERROR_MESSAGE
    • Outputs from a merge operator are qualified by the merge operator name. For example: MERGE_3.SYS.START_TIME_TIMESTAMP

  • For an OCI Data Flow task operator associated with an OCI Data Flow application, the outputs include any output parameters from the application, and the following output data types:

    • com.oracle.dos.task.model.customparameter.Arguments: args
    • Float:
      • bytesProcessed
      • bytesWritten
    • String:
      • applicationId
      • displayName

  • For a REST task operator, the following data types of REST response outputs are available:

    • JSON or JSON_TEXT: SYS.RESPONSE_PAYLOAD_JSON and SYS.RESPONSE_HEADERS_JSON
    • String: SYS.RESPONSE_STATUS
    Note

    • To use a REST response output in downstream operations, pass the output through an expression operator where you can apply string and regex operations. Then use the result in subsequent downstream task operators.
    • The String outputs SYS.RESPONSE_PAYLOAD and SYS.RESPONSE_HEADERS are deprecated. We recommend converting any existing usage to the JSON data type equivalents of SYS.RESPONSE_PAYLOAD_JSON and SYS.RESPONSE_HEADERS_JSON, respectively.

About the Parameters Panel

The Parameters panel shows all the user-defined pipeline parameters that have been created in a pipeline.

To access the Parameters panel when the pipeline is opened in the designer canvas, select Parameters from the View menu on the canvas toolbar.

Use the View tab to see the user-defined parameters in the pipeline. Used and unused parameters are shown. When you click the Used in link for a parameter that's used in the pipeline, the task operator referencing that parameter is brought into focus on the canvas.

Use the Config tab in the Parameters panel to delete a user-defined parameter or edit the default value.

Note

When you delete a user-defined pipeline parameter, any configured values in operators associated with the parameter are removed. To reconfigure an input value, see Configuring Incoming Parameters for Tasks.

Adding a Parameter in a Pipeline

You can add and define user-defined parameters on incoming parameters of task operators in a pipeline.

How you define a user-defined parameter depends on the type of the incoming parameter. For all parameter types, you provide a name and an optional description, and set a default value for the user-defined parameter. You can't change the type, and you can't change the name and description after the parameter is created.

A user-defined parameter can be reused within the same pipeline to represent the configured value for another incoming parameter of the same type.

  1. On the canvas of a pipeline, select a task operator that has one or more incoming parameters.
  2. In the Properties panel for the selected task, click Configuration.
  3. Next to Incoming parameters configured, review the number of configured and available incoming parameters.
    For example, 0/4 means that four incoming parameters are available in the task, and none have been reconfigured.
  4. Click Configure next to Incoming parameters configured.
  5. On the Configure incoming parameters page, review the input values that can be configured. In the row of the parameter type and value you want to add and assign a user-defined pipeline parameter, click Configure.
  6. On the Configure incoming parameter for <type> page that displays for the selected parameter, select Assign a parameter.
  7. Select Use user defined parameters, and then click Add parameter to create a user-defined parameter.
  8. In the Add parameter panel, enter a name for the parameter in the Identifier field.
  9. (Optional) Enter a Description to help identify the purpose of the user-defined parameter to other users.
  10. The Type field shows the type of the incoming parameter, which can't be changed.
  11. Set the default value for the parameter.
    How you set the default value depends on the incoming parameter type. For example, for a data entity, you use menus to select a data asset, connection, and schema, and then you select the entity.
  12. To create the parameter, click Add.
    By default, the newly created user-defined parameter is selected on the Configure incoming parameter for <type> page.
  13. Repeat the steps to add more user-defined parameters of the same type, if needed.

Viewing the Parameters in a Pipeline

You can view the system parameters that are available in a pipeline, and the user-defined parameters that you have created in a pipeline.

You can also use this procedure to see where a parameter is used in a pipeline.

  1. On the canvas of a pipeline, click any blank area.
  2. In the Properties panel for the pipeline, click Parameters.
  3. Select User defined or System defined.
  4. Review the list.
    The Used in column indicates where the parameter is used in the pipeline.

Assigning a Parameter in a Pipeline

You can assign existing user-defined parameters and system parameters to incoming parameters of task operators in a pipeline.

  1. On the canvas of a pipeline, select a task operator that has one or more incoming parameters.
  2. In the Properties panel for the selected task, click Configuration.
  3. Next to Incoming parameters configured, review the number of configured and available incoming parameters.
    For example, 0/4 means that four incoming parameters are available in the task, and none have been reconfigured.
  4. Click Configure next to Incoming parameters configured.
  5. On the Configure incoming parameters page, review the input values that can be configured. In the row of the parameter type and value you want to assign a user-defined or system parameter, click Configure.
  6. On the Configure incoming parameter for <type> page that displays for the selected parameter, select Assign a Parameter.
  7. Select Use user defined parameters or Use system parameters.
  8. Select an existing parameter from the list of user-defined or system parameters, then click Done.

    Only parameters of the same type as the incoming parameter are available for selection. If none is available, click Cancel.

    For a user-defined parameter, you can also click Add to create a parameter and then select it. See Adding a Parameter in a Pipeline.

Editing the Default Value of a User-Defined Parameter

At pipeline design time, you can quickly change the default value of an assigned user-defined parameter.

  1. On the canvas of a pipeline, select Parameters from the View menu on the canvas toolbar.
  2. In the Parameters panel, click the Config tab.
  3. Review the parameters listed by name.

    You can search the list by entering the full name of a parameter.

  4. In the row of the parameter value you want to change, select Edit from the Actions menu (Actions menu).
    The parameter data types that you can edit include NUMERIC, VARCHAR, DATE, DECIMAL, DOUBLE, FLOAT, INTEGER, TIMESTAMP, TINYINT, BOOLEAN, LONG, and STRING.

Unassigning a Parameter in a Pipeline

Unassigning a parameter removes only the reconfigured value of the incoming parameter. It doesn't delete the incoming parameter from the task or delete the user-defined parameter.

  1. On the canvas of a pipeline, select a task operator that has one or more incoming parameters.
  2. In the Properties panel for the selected task, click Configuration.
  3. Next to Incoming parameters configured, review the number of configured and available incoming parameters.
    For example, 2/4 means that four incoming parameters are available in the task, and two have been reconfigured.
  4. Click Configure next to Incoming parameters configured.
  5. On the Configure incoming parameters page, review the inputs that are configured.
    An input has a Default value. If the incoming parameter is reconfigured, the input has a Configured value. A configured value can be a user-defined parameter name with the reconfigured value shown in parentheses.
  6. To unassign an incoming parameter, click Clear.

Deleting a Parameter in a Pipeline

You can delete user-defined pipeline parameters that you no longer need in a pipeline.

System parameters in a pipeline can't be deleted.

  1. On the canvas of a pipeline, select Parameters from the View menu on the canvas toolbar.
    The View tab in the Parameters panel shows the user-defined parameters that have been created in this pipeline. If a parameter is used in a task, the Used in link shows the name of that task.
  2. In the Parameters panel, select Config.
  3. Select one or more parameters you want to delete, then click Delete.
    Note

    When you delete a user-defined parameter in a pipeline, any configured values in task operators associated with this parameter in the pipeline are removed. To reconfigure an input value, see Configuring Incoming Parameters for Tasks.