Combine Row and Columnar Storage in one Table to Optimize Database Performance.

Create a single table in which recent data is stored in a row-based format while older data is stored in a columnar format.

.. We use the gdelt dataset(link is external) containing hundreds of millions of news events as a reference. This use-case will benefit greatly from using row-based storage for recent data, and columnar storage for older data, so let’s see how we will be able to do this in PostgreSQL 9.5.

How to Make a Box-and-Whisker Plot in SQL

Flowing Data’s Nathan Yau does a great job of introducing box plots. As he notes, box plots typically graph six data points:

  • The lowest value, excluding outliers
  • The first quartile (this is the 25th percentile, or median of all the numbers below the median)
  • The median value (equivalent to the 50th percentile)
  • The third quartile (this is the 75th percentile, or median of all the numbers above the median)
  • The highest value, excluding outliers
  • Outliers