To write multiple CSV files using a loop based on column values

[CarlosEnrique84]

Here I want to share with you one solution to the problem of how to write multiple CSV files using a loop based on column values.

ForumQuestion0004 - Write Multiple CSV Files with a Loop – carlosenrique84

[ipazin]

Hello @CarlosEnrique84,

you have Group Loop for this use case. So you can avoid Group By and Row Filter nodes.

Something like this only updated to have nodes from newer versions:

Create Multiple Excel Files – ipazin

Additionally this topic is more suited for Knowledge Sharing

Br,
Ivan

[CarlosEnrique84]

Hi Ivan! Thank you for the feedback!

Carlos

[Startide]

Hijacking / necroposting :

I am trying to do something that I believe is similar, but fail to do so (so far).

I have a pretty big dataset, I want to filter it by “country” and output it as c:\path_to_file$$country$$.csv

I have copied your workflow, but can’t seem to filter the loop on the current country being read. What am I missing ?

EDIT : figured out the loop part, can’t choose a path though, it stores right in “my docs”, which I rather avoid thx for help

[CarlosEnrique84]

Please share your sample data and workflow.

[Startide]

That’s what it looks like. I figured out how to loop and output data to “ISO2.csv” for each country code I have.

What I can’t figure out is how to tell knime to write those excel files in a specific folder…

I am grabbing the hub (country) code and looping it to make a XX.xlsx filename variable

Then string to path (I think that’s the node I am missing something).

Then excel write :

[ipazin]

Hello @Startide,

these days I use a bit different design making use of Create File/Folder Variables node.

Take a look here (you don’t need SMB or any other connector node if you are writing data locally):

save file in online url sharepoint folder with dynamic name

Good evening, I have a flow and I can save a file with a dynamic address and a dynamic name in a local directory. I have built a string that cointains the file path+the name. I have then converted the string to path variable using the “string to path (variable)” node. The path variable results in the form: “C:\Users\username\company\main folder\subfolder\filename.xlsx”. The problem is when I try to save the file directly in the online sharepoint folder. In this case I would need a string l…

Br,
Ivan

[Startide]

That looks a lot more on point, I found a workaround with the string manipulation node by hardcoding my path in the variable :

join(“G:\docs\test new\”, $${SHub (#1)}$$, “.xlsx”)

I need to figure out how that node of yours works now

EDIT : can’t find that “variable expressions” node in my knime, is that an addon to install ? Also : how do you loop around with your example ?

[ipazin]

Hello @Startide,

you workaround seems just fine.

Variable Expression is part of KNIME Expressions extension. You can also see it here:

Variable Expression

To have it in a loop replacing String Manipulation (Variable) and String to Path (Variable) with 2 nodes I mentioned should be sufficient.

Br,
Ivan