SSB Flat-table Benchmarking
Star schema benchmark (SSB) is designed to test basic performance metrics of OLAP database products. SSB uses a star schema test set that is widely applied in academia and industry. For more information, see Star Schema Benchmark.
ClickHouse flattens the star schema into a wide flat table and rewrites the SSB into a single-table benchmark. For more information, see Star schema benchmark of ClickHouse
This test compares the performance of CelerData, Apache Druid, and ClickHouse against SSB single-table datasets.
Test conclusions
The test is performed on an OLAP table in a classic CelerData cluster, together with ClickHouse and Apache Druid, against the same dataset.
Based on the results from 13 queries performed on the 100 GB SSB-Flat dataset, CelerData has an overall query performance 2x that of ClickHouse and 5.1x that of Apache Druid. The unit of the results are milliseconds.
Test preparation
Hardware
CelerData, Apache Druid, and ClickHouse are deployed on hosts of the same configurations - AWS m7i.4xlarge.
| Spec | |
|---|---|
| Instance Number | 5 |
| vCPU | 16 |
| Memory (GiB) | 64 |
| Network Bandwidth (Gbps) | Up to 12.5 |
| EBS Bandwidth (Gbps) | Up to 10 |
Software
| CelerData | ClickHouse | Apache Druid | |
|---|---|---|---|
| Cluster Size | One FE, three BEs | Three nodes | One Master Server, one Query Servers, and three Data Servers |
| Version | 3.5.0 | 25.3.3.42 | 33.0.0 |
| Release Date | 2025.6.13 | 2025.4.22 | 2025.4.29 |
| Configuration | Default | Default | Default |
Test results
The following table shows the performance test results on 13 queries. The unit of query latency is milliseconds. All queries are warmed up 1 time and then executed 3 times to take the average value as the result. ClickHouse vs CelerData and Druid vs CelerData in the table header means using the query response time of ClickHouse/Druid to divide the query response time of CelerData. A larger value indicates better performance of CelerData.
| Query | CelerData | ClickHouse | Druid | ClickHouse vs CelerData | Druid vs CelerData |
|---|---|---|---|---|---|
| SUM | 924 | 1858 | 4710 | 2.01 | 5.10 |
| Q01 | 26 | 49 | 330 | 1.88 | 12.69 |
| Q02 | 16 | 31 | 260 | 1.94 | 16.25 |
| Q03 | 20 | 29 | 250 | 1.45 | 12.50 |
| Q04 | 133 | 197 | 420 | 1.48 | 3.16 |
| Q05 | 110 | 179 | 440 | 1.63 | 4.00 |
| Q06 | 60 | 158 | 320 | 2.63 | 5.33 |
| Q07 | 130 | 249 | 510 | 1.92 | 3.92 |
| Q08 | 83 | 197 | 380 | 2.37 | 4.58 |
| Q09 | 80 | 150 | 350 | 1.88 | 4.38 |
| Q10 | 16 | 33 | 250 | 2.06 | 15.63 |
| Q11 | 150 | 340 | 550 | 2.27 | 3.67 |
| Q12 | 60 | 133 | 330 | 2.22 | 5.50 |
| Q13 | 40 | 113 | 320 | 2.83 | 8.00 |