What the September 2021 DB‑Engines Rankings Reveal About the Shifting Database Landscape

DB‑Engines September 2021 Ranking Overview

DB‑Engines released its September 2021 database ranking, evaluating the popularity of 378 DBMSs and presenting the top‑30 list.

Decline Rankings

Compared with the same period last year, the three traditional leaders fell sharply. Oracle’s score dropped 97.82, taking the top spot on the year‑over‑year decline list. MySQL fell 51.72 year‑over‑year and 25.69 month‑over‑month, becoming the month‑over‑month decline champion, while its overall score continues to slide. Microsoft SQL Server fell 91.91 year‑over‑year and 2.50 month‑over‑month, ranking second on both decline lists.

Growth Rankings

MongoDB, a distributed database, rose 50.02 points year‑over‑year, claiming the top spot on the year‑over‑year growth list. Snowflake followed, gaining 49.39 points year‑over‑year and 5.53 points month‑over‑month, securing the month‑over‑month growth runner‑up. Notably, Snowflake jumped 86 places since September 2020, surging from a score of about 2.673 to 52.07—a nearly 20‑fold increase—making it a standout “black horse” in the data‑warehouse market.

Overall Analysis

While Oracle, IBM, and Microsoft have historically dominated the early domestic database market, the rise of domestic solutions such as DM (a fork of Oracle), Jushen (MySQL‑based), and TiDB reflects a growing talent pool and a shift toward a more competitive landscape. Nevertheless, Oracle and MySQL remain the most popular commercial and open‑source databases globally, with their lead continuing to expand.

Niche Databases Worth Noticing

Professionals can use DB‑Engines rankings as a reference; the rapid evolution of the big‑data era means new database products constantly emerge. For specialized requirements, lesser‑known databases may offer better fit than mainstream options.

Top Time‑Series Databases

InfluxDB, an open‑source high‑performance time‑series database, ranks first in the time‑series category, moving up one place to 28 overall with a 6.17‑point increase year‑over‑year. It excels at high‑throughput reads, writes, efficient storage, and real‑time analytics for massive time‑series data.

Top Key‑Value Databases

Redis leads the key‑value store ranking, praised for high performance, rich data structures, persistence, high availability, and distributed capabilities. This month Redis overtook Elasticsearch, surpassing Db2 with a 2.05‑point gain to rank sixth overall.

Emerging “Black Horse” Databases

ClickHouse, though relatively new, has seen explosive growth. Major companies rely on it for large‑scale analytics: Toutiao runs thousands of nodes handling dozens of petabytes and ~300 TB of daily raw data; Tencent uses it for game data analysis; Ctrip processes over a billion rows daily; and Kuaishou stores ~10 PB with 200 TB daily increments, achieving sub‑3‑second query latency for 90 % of queries.

ClickHouse’s ability to handle arbitrary metric‑dimension combinations in real time makes it a recognized “black horse” for modern OLAP workloads.