I do some stuff and then I want for each row to query the database and then exclude all rows from the workflow that are already in the database.
- I can not use Database looping as the actual query is a chemical structure query and not an IN() query
I created a table row to variable loop start and use the variable for a database reader and then convert that value to a variable used in Row Filter node. However this leads to an empty table error when no record is found in database. Using the empty table switch I get a different issue, namley in the loop end:
Variable Loop End Execute failed: Input table’s structure differs from reference (first iteration) table: different column counts 7 vs. 8
So how can I sanely do this? I mean this seem to me a very basic thing to do yet knime seems to make these overly complex…