This might help... The closest I got was this formula:
That should filter anything that was pulled with-in the last week but it returns 0 results.
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If your input were a server based data source that supports Custom SQL, you would be able to write the filter in the SQL Code. It would be something like:
WHERE [Date] = (SELECT MAX([Date]) FROM TABLE)
Since it is file based, you will have to do the filtering using some logic in the flow itself. One possible approach is detailed here: Latest Snapshot in Tableau and Tableau Prep (Maestro) | VizPainter
Hope that helps!
Yes it does, it confirms what I suspected. That it's not possible to do this in the Input Filter just yet.
I ran across that Latest Snapshot post in my searching and as I take it it would mean adding steps to the flow where I was hoping to do this on the first step since I figured that would increase performance since it wouldn't have to cache everything.
Maybe i'll add to the ideas.
1 of 1 people found this helpful
The interesting thing about performance in Tableau Prep is that there are two run modes: Design and Batch.
Here is my best guess: Design (where you are clicking steps and seeing the data profile change) would likely have a decreased performance (or at least increased memory usage) because it would cache the various steps along the way. However, Batch (where you run the flow to get an output) performance likely would not be impacted because it collapses the flow into an optimized query against the source - so the multiple steps turn into a single query that would somewhat resemble the query I wrote above.
I would definitely up-vote an idea for more robust filtering of the Input step as it would make the design experience more pleasant in some cases and would give me more control over potentially avoiding sampling.