1 Reply Latest reply: May 15, 2014 9:58 AM by Grant Perkins RSS

    External Lookup Error

    Zimkatz _

      Hi,

       

      Does anyone know what this error means?

       

      "The selected source columns do not form a unique key to the external table.  Do you want to continue by using data from the first instance of each key?"

       

      i get this error when i create an external lookup to an Excel file, after selecting the coloumns to link together.  The strange thing is, I cannot see any difference in my excel files and some of them get this error and some dont.  The ones that get the error dont always stop it working - sometimes it will still work.  I just want to understand what this error means to see if i can correct it.

       

      Any ideas?  :confused:

        • External Lookup Error
          Grant Perkins

          Hi,

           

          Basically it means that you don't have a unique key on which to perform a lookup - so there is some ambiguity with the possibililty that you get unexpected results. This could happen where a value in your table might link to more than one entry on you external look up table.

           

          This may be OK and acceptable for the lookup, or it may not, so the warning is provided but the user can decide to continue anyway. That is not a problem if you know and understand the data and can be sure that the results will not compromise your analysis.

           

          A favourite 'problem' for this message would be a table with blank entries looking up to an external lookup table which also has blank entries, possibly unintentionally blank.

           

          There can be other sources of the problem but it will almost certainly be something related to the contents of the lookup table in some way.

           

          HTH.

           

           

          Grant