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Showing posts with label join. Show all posts
Showing posts with label join. Show all posts

29.3.20

Concatenate Column in OpenRefine 3.0 and 3.3


We all know the pain of merging different columns in OpenRefine when you have null values. Before version 3.0, it required writing a complex GREL expression or managing multiple filters to ensure we are not losing any data. 

Those shortcomings have been addressed in the latest version! 

Starting OpenRefine 3.0, we have the coalesce() function:  which natively handles the null correctly. 

But evermore importantly, OpenRefine 3.3 introduced a user interface that offers tons of flexibility, including defining how you want to concatenate one or multiple columns together. 

I recorded a quick video demonstration: 

22.11.15

Limitation when splitting and joining multi-valued cells

Split multi-valued cells function helps to transpose data stored in one cells into multiple rows, while keeping the relationship with the other columns in the data set. In this article we will see some of the limitation of the function when splitting and joining back a data set and how you can work around it.