Hi Doug,
The easiest thing to do is to copy your production flow and set up a testing version of it, then you can test at your leisure by associating the data table to it. When we make changes to production flows, we always work in a test flow first. After we test and confirm the changes are working as intended, we propagate those changes to production on release night.
We don't have a sandbox though, so we just name test flows "XDEV_INSERT_NAME".
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Caleb Smith
Interstate Gas Supply, Inc.
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