1 Reply Latest reply on Feb 23, 2017 10:27 AM by Patrick Van Der Hyde

    initial connections to new data sources:  hiding vs filtering, setting up a template, exporting consolidated data

    Steve Schwantes



      1) I am looking to confirm the distinction between hiding a field as opposed to setting up (adding) a Data Source Filter.  I believe a filter is static or permanently applied to the data source (Iive or extract mode), while a hidden field can be dynamic; i.e., it's still in the underlying data source and can be later unhidden?


      2) I have downloaded several years of data from a Federal Government website; creating a separate Excel CSV file for each of last five years 2017 - 2013.  The parameters (fields or columns) for each file should be the same.  Each file has ~ 225 columns.  Of which I only want to retain ~ 55 columns.  So, for the first file I went through and just clicked on each column that I did not want to show and selected "Hide Field" (on the Data Source tab).  Then I created an extract for 2017 and the file size is quite manageable.  However, prior year file sizes go up to 10-15 Gb.  I connected to the 2016 file and then clicked on Add Filters and now it's been running for half hour with a message box saying:  "Loading the data source for the first time . . . . ".  May have to cancel out of this ... my question here is:  is it possible to use a previous batch of Data Source Filters in a separate and distinct Tableau work book?  Or would this be possible say if you connected to more than one data source in the same workbook ?  Okay it finally quit running that warning after ~ 35 ".


      3) For efficiency purposes ... was thinking I'd create a separate work book with a whittled down (Filtered Data Source or Hidden Fields) extract for each.  Then maybe blending into one workbook.  So then my final question is how can I go about the process of blending these 5 different data sources (reduced data sets from 225 to 55 columns) and export the data back out to a format that I can then import into a SQL Table (flat file, Excel CSV or other) - as there will be a need for matching to other data sets and appending within SQL.


      Thanks in advance for reviewing the above and any guidance / insights!!



        • 1. Re: initial connections to new data sources:  hiding vs filtering, setting up a template, exporting consolidated data
          Patrick Van Der Hyde

          1. - correct.  Hidden fields are still in the data unless you choose to extract and aggregate by the fields in the view.


          2. - are you using a Union to bring all of these files into Tableau at one time?   Using a wildcard union to bring them all in would allow you to hide or remove the data fields from import in one move and any new files dropped into the same directory would be imported on the next open.  Help covering this topic: Union Your Data 


          3 - Not sure you need to use blending and I wouldn't recommend it unless there is a specific use case for it..  These sound like csv files of data that are for different time periods but with the same fields in which case the wildcard union is a great way to manage them.


          I hope that helps





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