Download Tool Cannot Handle Null Value in FTP Download

[surendra_h]

We have a system which generated CSV files every data in a FTP Server. We have developed a Workflow in Alteryx to download these files to do some analysis.

Issue: We have noticed that the Download Tool does not read the complete file which contains empty string. It partially reads the file upto the location where the empty string is found. A sample data having empty string (5th Row,4th Column) is given below.

292219|1485|17|AN1931-992187|2020-07-14 09:03:46.920|40|0|1616|0.0|0.0|0|0
292218|1485|12|AN1931-992189|2020-07-15 23:49:56.047|40|0|2000|0.0|0.0|0|0
292217|1485|9|AN1931-992162|2020-07-13 13:52:46.260|49|1|917|0.0|0.0|0|0
292216|1485|17|AN1931-992187|2020-07-14 09:02:46.780|102|0|1616|0.0|0.0|0|0
292215|1086|4| |2020-07-16 08:23:34.000|27|1|466|0.0|0.0|0|0
292214|1485|9|AN1931-992162|2020-07-13 13:52:45.850|40|1|917|0.0|0.0|0|0
292213|1485|9|AN1931-992162|2020-07-13 13:52:45.373|102|1|917|0.0|0.0|0|0

292212|1485|17|AN1931-992187|2020-07-14 09:01:46.547|29|0|1616|0.0|0.0|0|0

The Workflow and the settings of Download Tool is shown below.

We tried downloading file as BLOB in the Download Tool. The files get fully downloaded but the BloB Convert Tool could not convert full file due the empty string.

Please let us know how to handle empty strings or any null values while downloading files from FTP using Download Tool. 

[danilang]

Hi @surendra_h 

A few points here

1.  You say that you're saving as a blob, but your config shows that the file is being download as a string.

2.  The output that you're using will write out the string that you've downloaded as a single field in the output file, along with any extra fields, such as the URL  and DownloadHeaders returned from the download tool.  If you've removed the extra fields in your select, the single string field will still be written with a column header and wrapped in an extra set of quotes.

If you need to save the file, configure the output tool to write "To a File".  This will strip out any extra fields and formatting and leave you with a csv file that can then be imported using an Input tool. 

Dan

[surendra_h]

Hi Dan,

Thanks for your reply.

I am reading a CSV file from FTP and I do not want to save it locally. Instead I want to read from FTP, process it and then publish it to tableau server.

I issue I am facing is, sometimes the the CSV fill will contain empty string in a column. While reading such files from FTP, the download tool does not read the file fully. Instead it reads till it encouters empty string and does not read the file further resulting in only partial file data in the workflow.

Original File:

Data read by the Download Tool in Alteryx:

Notice that the file is read till the record id with 699747 which has empty string in the fourth column.

[yzheng1001]

Hi,

I'm facing the same challenge here. When I download the csv file from the ftp server, the download tool reads the file till it encounters empty string and does not read the file further resulting in only partial file data in the workflow. Any suggestions? Thanks!