When adding columns from External data, it is currently not possible to match on columns that have been calculated in DXP.
This could be useful for several purposes:
* if casting of datatype is needed to perform the matching
* if string trimming is needed to perform the matching
* if calculations/tags are to be given a description by adding annotations
One of my customers is confused by that calculated columns are available in "from new data" but not available in "from original data".
From the customer's perspective there should be no difference between these 2.
I consulted with TIBCO support but couldn't get an reasonable explanation.
Please implement this.
Agree with the above commenters -- it may not be intuitive, but there are reasons for having both the Transformation (on data load) and the non-transformation (post data load) versions. I think it is handled adequately in code, but could be better explained/described in documentation or training.
I believe this is like this by design? Being able to join to a calculated column could produce an incredibly unstable report if anything was changed. The insert > transformation> calculate newccolumn method takes care of this requirement perfectly in my opinion
From what I can tell a reason you can use a "Transformed Column" and not a "Calculated column" is the calculated column could be altered during the Spotfire session where as a transformed column is static. Also, the calculated column may not "occur" until after data loading making it unavailable or non-existent at the time of data loading. Just some thoughts. There are times I wished I could use a calculated column but creating a transformed column as suggested by Brian has worked well.
Have you considered using Insert > Transformation > Calculate New Column ? In my experience if i use that method rather then insert calculated Colulmn I CAN use it for joining. I agree, i don't understand why there are 2 almost identical methods for inserting calculated columns.