Open Source Columnar Databases

Columnar databases are actually SQL databases with a different storage format where data is organised according to columns rather than rows. This is far more optimal for fact table queries.

If cloud hosting is a the only option, then the best solution is probably Amazon Redshift. However, if you need to install and operate your own the open source options (which have not been evaluated) are:

• CitusDB: http://citusdata.com/blog/76-postgresql-columnar-store-for-analytics
• MonetDB: https://www.monetdb.org/

If these are not suitable, there is also a commercial option in Infobright: https://www.infobright.com/