try to implement forward filling in mongo db

Working with Data
1

basically I have columns like column1, column2 and 3,4,5,6 etc.
so I wanted to group the data by column1 and order it by column2 then want to fill the nulls present in remaining columns on the base of there last present non null value in that group. I tried my best but in mongodb I’m not able to achieve expected result so please help me in this.

Thanks,
Swapnil Taware.

2

You could sort then group, pushing values from col + i to fields and then reduce those to pick the first or last populated values in the aray.

Do you have the query you have so far along with sample data and expected outcome?

What does the data look like in terms of volume and population?