0 Replies Latest reply on Oct 21, 2012 10:46 AM by Eric Meger

    Filter one data source using table from second data source

    Eric Meger

      I have two data sources. One has a list of data collected from sensors (several million records from 10s of thousands of sensors) along with the time stamp of each measurement. The second source has a list of several thousand sensors that are relevant to a particular analysis (TARGET LIST).

       

      I am trying to combine these two sources to determine how many measurements per day I received from each sensor but limited to only those sensors in the TARGET LIST.

       

      I edit the relationship between the two sources and lining the sensor ID. I can't seem to get the worksheets to calculate what I need.

       

      The TARGET LIST is an Excel sheet with with a table comprising a single column of SENSOR ID and about 8,000 ID numbers. I imported this into a Tableau extract.

       

      The DATA SET is a tableau extract with many columns of data, one of which is the SENSOR ID that gets linked to the TARGET list. Each row in the the DATA SET is a set of sensor readings with a time stamp, sensor ID and value for each of the columns.

       

      What I would like to get is a table as follows

       

      Sensor ID
      June 1
      June 2....
      1234# of measurements# of measurements
      12567# of measurements# of measurements
      2653# of measurements# of measurements

       

      In the end, what I REALLY need to get to is what percentage of the sensors in the TARGET LIST produces a measurement EVERY DAY in DATA SET.

       

      A convoluted couple of questions, I know. Sorry about that but any help would be appreciated.