Read the last line of a CSV file and extract one value in Knime

Question

I am working in a workflow on Knime, and I have an excel writer node as a final node of my workflow. I need to read this file and get and store the last value of one specific column (time). And with this data, I need to input in another time node, to update my API link to get a new request.

To summarize I need to extract specific information from the last line of my excel file in knime.

My question is: How can I read this file and get this value from my sheet? And then, how can update a time loop to refresh the data for inserting the current day in my API link?

UDDATE-> My question is how can I Filter always the last 90 days in my concatenate database. I have two columns in this file with dates. And I need to maintain just the last 90 days since the current day.

Answer 1

To read an Excel file, use the Excel Reader node.

The simplest way to get the last row of a table (assuming your date column has a value for every row of this table?) is probably to use a Rule-based Row Filter with the expression

$$ROWINDEX$$ = $$ROWCOUNT$$ => TRUE

Now you have a one-row table with the values from the last line of the Excel sheet. To help further we need to understand what you mean by update a time loop to refresh the date for inserting the current day in my API link . Can you update your question with a screenshot of your current KNIME code?