How do I add a column showing percentage of each school type in this example?
Whenever I add a custom column to calculate the percentage, it always just shows the first row with % instead of the whole list with a percentage.
Hi @irene
Create a Custom Expression in the Summarize-section instead of creating a Custom Column:
https://www.metabase.com/learn/questions/custom-expressions.html#custom-summaries
Hi @flamber. Thanks for responding. I'm trying to add a 3rd column to that table to show the % for each row and the "Share" expression is only calculating one value at a time and returning the results, e.g. I'd have to enter the following one at a time in the Summarize field:
Share([SchoolType] = "Alternative") * 100
Share([SchoolType] = "Elementary") * 100
How do I just enter one formula so it calculate a new column showing the % for each row?
Here's a video of what I'm trying to do whichm might be clearer. https://www.loom.com/share/1b73bc8bfe9b44129d7c43c6961431da
@irene Most databases doesn't have a simple way of doing this without sub-query or windowing.
Metabase currently cannot do windowing in the GUI, and sub-query would either require two questions if done in the GUI or you'll have to use SQL.
With SQL you would do something like this:
SELECT "SchoolType", count(*) AS "Count", count(*)/(SELECT count(*)::float FROM "School") AS "Percent"
FROM "School"
GROUP BY 1
ORDER BY 2 DESC
There's a request for making this much easier:
https://github.com/metabase/metabase/issues/2120 - upvote by clicking 
on the first post