I am a beginning Tableau user.
For our financial reports we have our monthly outlook files that contains data like:
SBU Name
Product Name
Date
Type (PO vs ACTL/OUTL)
Volume
COGS
Revenue
Version (the version of the outlook)
All files have the same lay out. I want to be able to combine all these files into 1 data set, so I can compare what has changed outlook over outlook, do forecast accuracy calculations by comparing what the outlook was for Month 2 with the actual result for Month 2, etc.
How do I blend/join these files so I can use them as 1.
If you're talking about the EXACT same layout (exact same column names, etc.), but with different months for each file (are these Excel data sources?), then you can use a UNION, as described here:
http://mkt.tableausoftware.com/files/tips/pdf/tip1001.pdf
Another option from a related thread: http://community.tableau.com/thread/131751
More info: Combining Multiple Data Sources into One View | Tableau Software
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