Example:
dbadmin=> SELECT c1 a_date,
dbadmin-> count(*) cnt
dbadmin-> FROM some_data_2_chart
dbadmin-> GROUP BY 1
dbadmin-> ORDER BY 1 DESC;
a_date | cnt
------------+---------
2019-03-20 | 7600474
2019-03-19 | 4254718
2019-03-18 | 7327122
2019-03-17 | 8274362
2019-03-16 | 6151465
(5 rows)
dbadmin=> SELECT c1 a_date,
dbadmin-> COUNT(1) cnt,
dbadmin-> REPEAT('*', (50 * COUNT(1)/MAX(COUNT(1)) OVER ())::INT) chart
dbadmin-> FROM some_data_2_chart
dbadmin-> GROUP BY 1
dbadmin-> ORDER BY 1 DESC;
a_date | cnt | chart
------------+---------+----------------------------------------------------
2019-03-20 | 7600474 | **********************************************
2019-03-19 | 4254718 | **************************
2019-03-18 | 7327122 | ********************************************
2019-03-17 | 8274362 | **************************************************
2019-03-16 | 6151465 | *************************************
(5 rows)
It’s a lot easier to visualize the differences in row counts when viewing them as a chart column!Helpful Links:
https://www.vertica.com/docs/latest/HTML/Content/Authoring/SQLReferenceManual/Functions/String/REPEAT.htm https://www.vertica.com/docs/latest/HTML/Content/Authoring/SQLReferenceManual/Functions/Analytic/MAXAnalytic.htm https://www.vertica.com/docs/latest/HTML/Content/Authoring/SQLReferenceManual/Functions/Aggregate/COUNTAggregate.htm
About the Author
James Knicely
Vertica Field Chief Technologist
I've had the privilege of working with many database technologies in my career. But after being introduced to Vertica in May of 2011 as a client, I was hooked on the new technology after witnessing a query run in milliseconds that had previously ran for hours on the legacy database we had in place. It was then that I knew I wanted to eventually join the Vertica team, and 4 years later I did! I am currently a Vertica evangelist and am ready to help you get on board! Please feel free to reach out to me with any questions you have about Vertica and make sure to follow my Vertica Quick Tips!
