Significance of SOURCE_ACTION_ID in pay_payroll_rel_actions table

Summary:

Hi,

At the time of using table pay_payroll_rel_actions , we generally put this condition in where clause: SOURCE_ACTION_ID is not null.

I observed that in table (pay_payroll_rel_actions) we will have two rows one row with blank source action id and one with data in source action id.

I want to understand what is the significance of source action id in table pay_payroll_rel_actions?

Thanks.

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