It's probably the same for a non wildcard... Trying to find a way to make sure that new text files are added to the union when they are added to the folder. I could just refresh the extract once a day, but I don't want to have to re-run the entire union everyday.
Will Tableau scan the folder and only add new files to the union or will it re-run the entire thing - if I refresh the extract?
I tested this out since I use wildcard with a bunch of google analytics files that I collect monthly.
If you have an extract, a refresh of the extract (just right click on the extract and select 'refresh data' ) and it will pull in the new files. This was very speedy in my test but looking at a performance recording and test where I removed files from the directory, I believe the query for the data source is doing a full refresh from the files in the folder on an extract refresh.
If a live connection is utilized, then Tableau will utilize any new files placed into the wildcard file location on restart or by using a refresh of the data source.
If you prefer to just add one file at a time, I suggest using the 'append data from a file' feature from the data extract menu.
I hope that helps you out.
I tried it this morning and it looks like it did a full refresh. It's doable, but takes a little longer than I would like. I do wonder if I could utilize incremental refresh, but I don't know much about that. Does it scan through one field and look for updates to it?
Thanks for the help
Have figured this one out?@
I also have a daily auto-added CSV file to a specific folder, with a naming convention to be picked up by the wildcard feature.
Does it make a difference for live vs extract?
Does it make a difference if the folder is Google drive / local / network?
Does it make a difference tableau DT or server workaround?