Ranking > Method
Method of calculating the scores of the DB-Engines Ranking
The DB-Engines Ranking is a list of database management systems ranked by their current popularity. We measure the popularity of a system by using the following parameters:
Number of mentions of the system on websites, measured as number of results in search engines queries. At the moment, we use Google, Bing and Yandex for this measurement. In order to count only relevant results, we are searching for <system name> together with the term database, e.g. "Oracle" and "database".
General interest in the system. For this measurement, we use the frequency of searches in Google Trends.
Frequency of technical discussions about the system. We use the number of related questions and the number of interested users on the well-known IT-related Q&A sites Stack Overflow and DBA Stack Exchange.
Relevance in social networks. We count the number of Twitter tweets, in which the system is mentioned.
We calculate the popularity value of a system by standardizing and averaging of the individual parameters. These mathematical transformations are made in a way so that the distance of the individual systems is preserved. That means, when system A has twice as large a value in the DB-Engines Ranking as system B, then it is twice as popular when averaged over the individual evaluation criteria.
In order to eliminate effects caused by changing quantities of the data sources themselves, the popularity score is always a relative value, which should be interpreted in comparison with other systems only.
The DB-Engines Ranking does not measure the number of installations of the systems, or their use within IT systems.
It can be expected, that an increase of the popularity of a system as measured by the DB-Engines Ranking (e.g. in discussions or job offers)
precedes a corresponding broad use of the system by a certain time factor. Because of this, the DB-Engines Ranking can act as an early indicator.
We spent a considerable amount of effort to optimize our method of measuring popularity. We are able to combine data sources with very different statistical properties in a way that makes all significant trends visible in a well-balanced overall score. We can handle missing and erroneous data, we can deal with spikes and fluctuations. Data collection is done automatically to a large extend.
Very notable organizations have licensed our ranking technology to apply it in their own domain, and so can you. Contact us if you want to know more about options to use our well-tried and proven methods for your own business.