Counter Restart when row value change

[ecamerin]

Dears,
I would like to create a counter that reset to 1 when the value in a row change.
for example when proposal_id or category change then the row counter should restart to 1
proposal_id, category, row_counter
1, A, 1
1, B, 1
1, B, 2
1, C, 1
1, C, 2
2, C, 1
2, C, 2
2, D, 1
3, A, 1
3, A, 2
3, A, 3
4, A, 1

thanks

[elsamuel]

Using the idea from here:

The new_counter column is what’s been generated.

[gonhaddock]

Hello @ecamerin
You can achieve the task with a single node by using ‘Rank’ node.

Rank

The node can be configured with the option ‘Ordinal’ by using Grouping Attributes section.

BR

[ecamerin]

Thank @elsamuel works great

[ecamerin]

thanks I’ll give a try

[gonhaddock]

@ecamerin
At the end it’s necessary an extra column that can be ANY (could be the INDEX, a copy of your category column…), this happen because your logical OR condition on the column counter change.

@ecamerin

reset to 1 when the value in a row change

Therefore, aiming to configure the ‘Rank’ node you need to include both columns in the ‘Grouping Attributes’ section, and the node doesn’t allow to rank a column that’s been already included in the Group; in this case I will use the starting created one (instead a combiner or aggregation).

But as summary, no looping is needed in this task.

BR