I need to persist some objects into my database and the quickest way seemed to be to convert them to JSON, then save that. That works ok with a Dataset, but fails on an object that contains a Dataset. d = system.dataset.toDataset(["foo"], [[1]]) print system.util.jsonEncode(d) # {"columns":[{"name"…

Relevant thread. Looks like encoding the dataset first may work. [image] [BUG-15901] JSON encoding and decoding a "Dataset" datatype property Ignition I am trying to pass a value of “Dataset” type as a value in a dictionary which I need to store in a “String” f…

I can’t remember when it changed but a Dataset is now also interchangeable with a pyDataset. Encode the dataset then add it to the dict as json, then it should work. I believe the conversion may not work correctly unless it can detect the Dataset type directly.

That happened when the version 8.1.x jumped to 8.3.x. If on 8.3 and below, this does not apply. <a href="https://www.docs.inductiveautomation.com/docs/8.3/getting-started/installing-and-upgrading/ignition-8-upgrade-guide/81to83-upgrade-guide#system-function-changes-and-deprecations:~:text=Note%20that%20this%20function%20has%20been%20deprecated%20because%20datasets%20no%20longer%20need%20to%20be%20manually%20wrapped%20as%20PyDatasets.%20This%20change%20also%20impacts%20system.dataset.toDataSet%20from%208.1%2C%20which%20now%20has%20only%20a%20single%20syntax%20and%20should%20be%20written%20as%20system.dataset.toDataset%20in%208.3." rel="noopener nofollow ugc">Link to change

Yeah, so far that seems to be the only solution. My problem with that approach is now you don't have an object containing a dataset, you have an object containing a string representation of a dataset, which you can then encode to JSON. That means you can't cleanly go backwards. I mean, if you want t…

There is essentially no penalty for converting to a pyDataSet. I would just do that. I would probably write a wrapper functions which traverse the object and convert all the datasets prior to calling jsonEncode, then then do the oposite calling jsonDecode and then traversing the object and convert…

StackOverflowError on jsonEncode of dict containing Dataset

Ignition

AIO October 8, 2026, 8:20pm 2

Relevant thread. Looks like encoding the dataset first may work.