bar-chart.md

Bar chart

Explore this snippet with some demo data here.

Description

Bar charts are perhaps the most common charts used in data analysis. They have one categorical or temporal axis, and one numerical axis. You just need a simple GROUP BY to get all the elements you need for a bar chart:

SELECT 
   AGG_FN(<COLUMN>) as metric,
   <CATEGORICAL_COLUMN> as cat
FROM 
   <PROJECT.SCHEMA.TABLE>
GROUP BY
   cat

where:

• AGG_FN is an aggregation function like SUM, AVG, COUNT, MAX, etc.
• COLUMN is the column you want to aggregate to get your metric. Make sure this is a numeric column.
• CATEGORICAL_COLUMN is the group you want to show on the x-axis. Make sure this is a date, datetime, timestamp, or time column (not a number)

Usage

In this example with some Spotify data, we'll look at the average daily streams by month of year:

select
  avg(streams) avg_daily_streams,
  format_date('%m - %b', day) month
from (
  select sum(streams) streams, 
  day 
  from spotify.spotify_daily_tracks
  group by day
)
group by month