Dropping Variables from the Pipeline
You can remove a variable from Pipeline In or Pipeline Out by dropping the variable. You can drop variables to eliminate pipeline variables that are not used by subsequent services in a flow. Dropping unneeded variables reduces the size of the pipeline at run time and reduces the length and complexity of the Pipeline In and Pipeline Out displays, which can make the Pipeline view much easier to use when you are working with a complex flow.
Keep the following points in mind when dropping variables from the pipeline:
You can only drop variables from
Pipeline In and
Pipeline Out. In a MAP step, you can only drop variables from
Pipeline In.
Once you drop a variable from the pipeline, it is no longer available to subsequent services in the flow. Do not drop a variable unless you are sure the variable is not used by services invoked after the point where you drop it.
At run time,
Integration Server removes a dropped variable from the pipeline just before it executes the selected service (if you drop a variable in
Pipeline In) or immediately after it executes the selected service (if you drop a variable in
Pipeline Out).
If you drop a linked variable from
Pipeline In,
Integration Server executes the link
before it drops the variable. However,
Integration Server server does not link a null value to the destination variable.
You cannot drop a pipeline variable if the variable has a fixed null or default value assigned.
Designer uses the
symbol next to the variable icon to indicate that the variable has a fixed value that you cannot override by linking it to another variable.
You cannot drop a pipeline variable in a child flow service if the variable exists in the parent flow service. That is, a child flow service cannot drop an “upstream” variable.
To drop a variable from the pipeline
1. In the flow service editor, select the INVOKE or MAP step whose pipeline variables you want to drop.
2. In the Pipeline view, select the variable that you want to drop.
3. Click 
on the toolbar.