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Here we used "AND next filter" on the first row to find devices containing both an "m" and a "y". On the third row, we use the "OR all previous filters" to mean that all of the previous filters must be considered as one.
Example 5: Publish data for all devices that have both an "m" and a "y" but do NOT have
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a "
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p"
Here we needed to "AND next filter" all three. Had we used "OR next filter before the record with the "P", it would have returned devices containing an "m" and a "y" and ALSO all devices that do not contain a "p" (whether or not they contain an "m" and a "y")