our use case is that an analyst will use the the production line built by another user and it will create a table that will be written to Oracle.
The analyst will create tables as temporary files or as permanent table. An temporary table is identified by the comment. So if the table comment is empty it is temporary, if it is filled it will be kept.
We are using production line variables for the user to insert the name of the table and also to write a comment. So for a temporary table the user would not fill the variable, but for a permanent table he would.
We do use a default value at the moment for the analyst to use, but it leads to organizational changes, because the deletion logic from Oracle will also have to be adjusted.
since a Production Line/Workflow is triggered to write the table, you could also overwrite the default value again in e.g. the Extended Mathematical Operation Processor in an extra or one of the existing Workflows, if I understood your setup correctly.
Statement would then be
WHEN comment_column = "<default_value>" THEN ""
In that case you should define a default value that will most likely not be used as comment, of course.
It will result in an empty STRING and the Oracle deletion logic could remain unchanged.