group by - row counting


i'm quite new with Knime. I have a dataset composed by products reviews made by different users.

I want to add a new colum in which I want to express the level of each user, according to the numer of reviews done. 

I tried using a constant value column and group by nodes. 

Than i used a rule engine node to classify them ( =1 "one time reviewer"; >1 "hard reviewer"). 

How can I append this column to the whole dataset?

I hope that i have been clear. 

thanks for the support



P:S See attached the dataset. The column is "user ID" ( i want simply create a new variable according to the numer of reviews done by each user).

Hi Valeria,

you can e.g. join the column back to the original data set by usig the user id as joining column.

Cheers, Kilian

thanks a lot Kilian.

is it possible to extract a table from a node as an excel file? 



Hi Killian thanks a lot.

i was wondering how can i convert the output od a node into an excel file?

is it possible?

thanks a lot


Hey Valeria, 

you can save the table with the CSV Writer note. Use "\t" as data seperator in the advanced tab of the CSV Writer to get a tab delimited file. If you start Excel now, you can go to "Data" > "From Text" and import the CSV-File.



Hi Valeria,

there is also a XLS Writer node that writes tables directly as excel files.

Cheers, Kilian