we have experienced a strange behavior of KNIME 2.8 after copy/paste of nodes. It is weired and some things are not easy to reproduce, but it was found by two users on MAC:
a) if a couple of nodes of a pipeline are copied and pasted, e.g. for following up the second output of a Row Splitter in the same way as for the first output, then the output tables of nodes following the second output actually show the data of the first pipeline. The stange thing is, that the table dimensions that you see by mouse-role-over on the output port is different (correct) compared to what the table displays when opening the output. It looks like the output table displays different data than what the nodes' output data actually is. This is very worrisome! Anyway, if you reset some nodes upsteam or close and reopen the worflow the re-excecution does what it should. Unfortunately I dont have an example to really reproduce this for now, but at least for ...
b) I found a way to reproduce it, do this:
- File Reader load KNIME's Iris data set (see data = 150 rows)
- drag and drop Row Filter, exlude, from column class, "Iris-setosa" (see data = 100 rows)
- copy/paste this Row Filter, exlude, from column class, "Iris-versicolor" (see data = 50 rows, keep table open!)
- paste Row Filter, connect => node stays red
- configure this node => Error: "The dialog cannot be opened for the following reason: Cannot be configured without input table" (data of previous node is still visible in table!)
- upon reopening output table of the previous node, all of a sudden the data disappears and "No data available!" appears
- saving, closing, reopening the workflow, this node was green, now also becomes red
- configure, ok, the workflow executes as expected.
If you instead drag 'n drop the Row Filter from node repository, everything is ok. Copy/paste looks like loosing conntection to some temp data in the background. During some tests for this I also for this error message in the console, which was actually from different open workflow I was not (!) working on:
ERROR FileUtil Temp folder "/var/folders/3+/3+bZ1tbnFYyIMc4STi2l1U+++TM/-Tmp-/knime_Browse_TDS_DB89850" does not exist (associated with NodeContext "Row Filter 2:117 (EXECUTED)") - using default temp folder ("/var/folders/3+/3+bZ1tbnFYyIMc4STi2l1U+++TM/-Tmp-"
I hope you can somehow reproduce this and fix the problem, because copy/paste is very important!