September 2021 DB‑Engines Ranking: Who’s Falling, Who’s Rising?

DB‑Engines September 2021 Ranking Overview

DB‑Engines released its September 2021 database ranking, evaluating 378 DBMSs. The top‑30 list is shown below.

Decline Rankings

Oracle fell 97.82 points year‑over‑year, taking the “largest drop” title. MySQL dropped 51.72 points year‑over‑year and 25.69 points month‑over‑month, becoming the monthly decline champion. Microsoft SQL Server fell 91.91 points year‑over‑year and 2.50 points month‑over‑month, ranking second in both categories.

Rise Rankings

MongoDB increased 50.02 points year‑over‑year, winning the “largest yearly gain”. Snowflake rose 49.39 points year‑over‑year and 5.53 points month‑over‑month, securing the monthly gain champion and second place in yearly gain.

Snowflake’s ranking jumped 86 places since last year, with its score soaring from about 2.673 to 52.07, a nearly 20‑fold increase, marking it as a “dark horse” in cloud data warehousing.

Overall Analysis

Traditional giants such as Oracle, IBM and Microsoft have long dominated the early domestic market, but the rise of domestic solutions like DM, TiDB and others signals a move toward a more competitive landscape. Despite this, Oracle and MySQL remain the most popular commercial and open‑source databases globally.

Niche Databases Worth Noticing

Specialized databases can better meet unique requirements when mainstream options fall short.

Dark Horse: ClickHouse

Although relatively new, ClickHouse has seen rapid adoption. Major companies use it for large‑scale analytics:

ByteDance runs thousands of ClickHouse nodes, handling tens of petabytes and 300 TB of daily raw data.

Tencent employs ClickHouse for game data analysis with a dedicated monitoring system.

Ctrip has over 80 % of its business on ClickHouse since July 2018, processing billions of rows daily.

Kuaishou stores about 10 PB, adding 200 TB daily, with 90 % of queries completing under 3 seconds.

ClickHouse is recognized as a real‑time OLAP database capable of handling arbitrary metric and dimension combinations efficiently.

Recommended Reading

Database System Concepts (7th Edition) – A comprehensive guide covering theory and practice.

DBA Handbook: Oracle and MySQL – In‑depth operational methodologies for both systems.

Database Internals – Full‑stack view of modern database technology.

Effective Database Optimization – Architecture, standards, and SQL techniques.

Redis Development and Operations – Practical insights into Redis at scale.

InfluxDB: Principles and Practice – Time‑series database expertise with real‑world cases.

ClickHouse: Theory and Practice – Authored by core contributors, a definitive guide.

HBase: Principles and Practice – Detailed coverage by PMC members and engineers.

PostgreSQL Mastery (2nd Edition) – Advanced features and production case studies.

MySQL Technical Deep Dive – Expert analysis of InnoDB internals and performance.

This analysis aims to help database professionals choose technologies that best fit their business needs, rather than relying solely on ranking positions.