Hi Marco,

I guess looking at the emails between myself and Wolfram Technical Support that it was StackExchange that accepted it as a bug. Wolfram Technical Support: "This particular issue has been filed as a report and our development group is working on solving it for a future release. The introduction of this behavior comes from the reworking of CSV importing in Mathematica 11.2 and, as some of your posts mention, the workaround is to not specify {"Data", All} when all of the data needs to be imported."

I replied back that this was a broader issue, asked that it be raised to a higher supervisor, and copied Steven Wolfram on the email chain:

"If you export/import CSV data in Mathematica 11.2, no truncation of rows happens and the TextDelimiters parameter is not needed. But all CSV files exported in earlier releases of Mathematica, like release 11.1, are subject to hidden row truncation. So all user CSV files storing critical data are at risk. You can't tell 100,000s of existing Mathematica users, to update every program that imports CSV files created from previous Mathematica releases. You have to fix this. The default behavior should be, all existing Mathematica import/export CSV works as it always has, and newer Mathematica CSV functionality can be utilized by adding additional parameters. Not the other way around.

The same is true with the long elapsed time issue.

Please raise this to a higher supervisor.

You have to fix this.

Just some additional comments on this issue:

1. You should halt all further downloads of Mathematica 11.2 until this issue is fixed in Mathematica 11.3

2. This issue may apply to other file types, not just CSV files. You are going to have to test that.

3. If you have a multimillion dollar financial or drug company that heavily relies on and uses Mathematica for simulations and financial forecasts, they should not rollout Mathematica 11.2 in their production and tests environments until this issue is fixed. You have no idea what hidden data truncation will have on simulations and financial data. And you can't take that chance, whether it's one file, one user, or hundreds of thousands.

4. If I export 10,000 rows of data, I better get back 10,000 rows of data on import. Whether a data field has missing or questionable values is not the issue. Most coding will filter or throw out bad data. But an export/import should return all rows. "

Hi Joseph,

I don't have sufficient experience communicating with the Wolfram tech support team but from their replies cited in other questions on StackExchange I assume that the formulation

This particular issue has been filed as a report and our development group is working on solving it for a future release.

actually means that the tech support team accepted the issue as a bug. But it doesn't necessarily mean that the development team considers this issue as a bug: for example, in the case of this unrelated issue the support confirmed the bug at first but later stated that the development team considers new behavior as correct.

The default behavior should be, all existing Mathematica import/export CSV works as it always has, and newer Mathematica CSV functionality can be utilized by adding additional parameters.

I agree. At very least, they should add a documented Method option allowing correct import of CSV files generated by previous versions of Mathematica.

This issue is now recognized as a bug in Mathematica 11.2.

See the below link:

Bug Introduced In Mathematica 11.2

Hi again Marco! Now this statement looks interesting. I will have to try it! The thing is, I still want that conversation with Wolfram technical support. Without that "TextDelimiters"->"" parameter, CSV file Imports under Mathematica 11.2 are loosing/truncating data. Without anyone being aware of it. That should never, never happen. Even if there is a parameter fix, like "TextDelimiters"->"" available, it should not be left to the hundreds of thousands of users of Mathematica, to discover the problem, and fix every CSV Import statement across every program they have. No, this needs to be fixed by Wolfram ASAP, before many, many users run into the same issue. And while they are at it, Wolfram should also fix the Import elapsed time problem, again, not leaving it to their user base to modify all their CSV Import code. I've done my part and opened a problem record on this with Wolfram. Waiting for their call.... Best Regards!!!

Hi Ivan, On your first reply, I've been using that version of the Import statement on CSV datasets for a while, across different versions of Mathematica with no issues, until Mathematica 11.2. There were two issues with the Import statement under that newer release. The first was that it truncated rows of data on an import without any notification, unless you were looking for it with a Length function. The"TextDelimiters"->"" fixed that problem in Mathematica 11.2, but it should of never occurred, and will impact other users, without them realizing it. The second issue is the 100 times increase in elapsed time. I've just opened a bug report with WolfRam.