Pipeline to update multiple records?

I am sure this is possible, but not sure of the mechanics.  I need to insert an order number into multiple records in a separate table when a value is entered in a specific field.  For example, suppose I  enter a date in a field Table A and entering that date triggers the pipeline I want to insert an order number in a different field where Field X is equal to Field X in Table B.  What is the best way to create a pipeline to preform this task?

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Paul Peterson
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