Enabling 'Function' features in 'Custom Column'

Hi Metabase!

I've a request of enabling the 'Function' feature in 'Custom Column', so I can make a column of specific aggregations which will be available at the every row for summarizing the each element. And also it'll make the custom column to auto-increment when there is an update in the column which was functioned to that custom column.

Example: I've a table of customers with number of products viewed(I've to aggregate the total number of products viewed grouped by customer ID, now you can get the problem). I want to find the number of products yet to be viewed. So if I've the column of total number of products. I can make the difference.

Hi @SaravananJP
You would need to do the aggregation separately and join in the data - example Listing zero values in a question
Custom Columns are part of the SELECT-clause, whereas Custom Expressions can be used in the aggregation.
https://www.metabase.com/docs/latest/users-guide/expressions.html