Columnar databases have existed since the 90s, but came to prominence after the release of Google Bigtable as mentioned earlier. They are, in essence, a method of storing data that is optimized for querying very large volumes of data in a fast and efficient manner relative to row-based/tuple-based storage.
The benefits of columnar databases, or more concretely storing each column of data independently, can be illustrated with a simple example.
Consider a table consisting of 100 million household addresses and phone numbers. Consider also a simple query that requires the user to find the number of households in the state of New York, in the city of Albany, built after 1990. We'll create a hypothetical table to illustrate ...
