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How to pass values to a child snap

ADORAISWAMY
New Contributor II

I am a newbie to Snaplogic. I am developing a pipeline to copy data from Oracle tables to Snowflake using Snaplogic. I have created a parent pipeline and used “Pipeline Execute” to pass values to the child pipeline. I am having trouble understanding the concept of parameters, fields, $, _, _$. Everything is confusing me to the World’s end. I wish there was proper documentation for that.

The parent pipeline works perfectly and it displays data as expected. But I don’t know how to pass those values to the child pipeline. I have attached the pipelines here.

Please help me understand how the whole parameter concept works in Snaplogic.
Parent_2021_06_17.slp (6.6 KB)
Child_2021_06_17.slp (29.7 KB)

9 REPLIES 9

ptaylor
Employee
Employee

It looks like you’re very close. You just need to enable the expression button toggle (=) for the first and third expressions in the Mapper at the beginning of the Child pipeline:
Screen Shot 2021-06-17 at 1.14.19 PM

ADORAISWAMY
New Contributor II

Hi Taylor.
Thanks very much for replying. I made the change as you suggested but the output view in the child mapper doesn’t show the data as expected, even though it validates “green”. Is that expected or I am mistaken?

Screen Shot 2021-06-17 at 12.35.21 PM
Screen Shot 2021-06-17 at 12.35.36 PM

Hi. Unfortunately our UI doesn’t support a way to preview the output of snaps in a child pipeline when executed from the parent pipeline, so what you’re doing here is just executing the child by itself, correct? When you do that, the values of the pipeline parameters that the Mapper is referencing aren’t coming from the parent pipeline; they are just the default values of the pipeline parameters:

Screen Shot 2021-06-17 at 2.02.17 PM

ADORAISWAMY
New Contributor II

Hi Taylor,
I am actually executing the parent pipeline. So, shouldn’t the child mapper display proper data? Thanks again and your quick response is much appreciated.