Parsing DownloadData Blob for Size in Bytes to throw a Message/Warning/Exception

[mbogusz]

Dear Majestic Alteryx Community,

I'm trying to get the Message tool to throw a Warning/Error if the DownloadData blob size is 3 Bytes or less.  I'm having a hard time figuring out what to do and if there's a way to filter the raw DownloadData column (a blob data type) for the Message tool to trigger something.

Example of the flagged DownloadData that I'd like a Message thrown:

Example of the non-flagged DownloadData row that doesn't need to throw an exception:

Since DownloadData isn't a string data type I'm having a hard time filtering it for 3 bytes or less.  Any suggestions?

Thanks,
Matt

[BrandonB]

I think that the Field Info tool should help you with this found in the Developer category

 

[mbogusz]

Hi @BrandonB, I tried using the Field Info tool and it's showing the blob data type size for the field only (I guess 2147483647 is the default).

Formula tool that shows the field size:

Same size as in the Field Info tool:

I'd like to be able to filter the DownloadData column for blobs <=3 bytes and if there are rows/blobs like that, then those would filter into the Message tool and trigger a warning/error message to appear. 

[jdunkerley79 · Accepted solution]

One approach is to use a Blob Convert tool. Convert it to a hex string, then you can use a formula tool to compute the length:

This isn't perfect as does involve converting the blob but don't think any other direct way.

Sample attached

[mbogusz]

Thank you @jdunkerley79!