Rule-based Row Filter doesn't work

Hello everyone!

I’m using KNIME to automate some processes and I’m attempting to clear my table of some premises that shouldn’t be there. However, the rule-based row filter ignores the code and just sends out the exact same table as before. What I was coding looks like this:

$column1$ IN (“parameter 1”, “parameter 2”, “parameter 3”) => FALSE
TRUE => TRUE

  • Includes TRUE matches

The idea is that the rows that have parameters 1, 2 or 3 are excluded from the end table. The node executes as normal and does not send any errors to the console, but when I preview the table, the rows with parameters 1, 2 and 3 are still in. This is especially upsetting me because I’ve done similar rule-based row filters in the past (with the exact same syntax with the exact same purpose) and it worked as expected before.

Thanks in advance!

1 Like

KNIME is case sensitive. Please check if your data is the same as before.

Yes, it is. I’ve checked for mispellings, errors in the selected column, anything like that, and it still doesn’t filter :confused:

Try to switch to Column Expression node.

I don’t think that would work for this case. Column Expressions appends a column, instead of filtering rows.

You can filter on added column. Just to make sure that your data is correct. Also, restart KNIME if you did not do this yet. Check for extra spaces, invisible symbols and such.

1 Like

Hi there @GiPiconi,

welcome to KNIME Community!

Have you managed to figure it out? If not can you share simple example where this can be seen?

Br,
Ivan

Hello @ipazin ! Thanks for the warm welcome ^^

Because this was a bit of a time sensitive issue, and I could not figure out what was wrong with the code, I gave up using the node and figured a way around it (I executed the step in a different part of the flow, utilizing other nodes that have not given me trouble so far). I might try to offer an example later if I can, but I believe it might be a glitch that I got lucky enough to find (multiple times, in different flows, even. Lucky me!), especially because sometimes it works gracefully and sometimes it gives me trouble like this.

Thanks everyone for the offered support and suggestions!

1 Like

Hi @GiPiconi,

glad you found a workaround and if you manage to create an example workflow I will definitely take a look at it and check is it a bug or miss configuration :wink:

Br,
Ivan

Hi GiPiconi,
I had similar problem with filtering using Rule-base Row Filter node.
This node better works with positive indication, so your code shud look sth like that:
$column1$ IN (“parameter 1”, “parameter 2”, “parameter 3”) => TRUE
Exlude TRUE matches.
Hope this help.

2 Likes

Hi there @piotr_domagala,

give me example! - I’m not saying there is no bug in this node I just refuse to accept randomness in this case (and probably in general) :smiley:

Br,
Ivan

I havent ever discover why this particulsr node works that way. Many times i used it in way i described and achived desired goals.

Cheers.

Piotr.

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