A new company just emerged from stealth mode yesterday, called Dremio, backed by Redpoint and Lightspeed in a Series A funding of $10m back in 2015. The founders came from MapR, but were active in Apache projects like Drill and Arrow. The same VC’s backed MapR and had the Dremio founders work out of their facilities during the stealth phase. Now the company has around 50 people in their Mountainview, California office.
Apache Drill acts as a single SQL engine that, in turn, can query and join data from among several other systems. Drill can certainly make use of an in-memory columnar data standard. But while Dremio was still in stealth, it wasn’t immediately obvious what Drill’s strong intersection with Arrow might be. But yesterday the company launched a namesake product that also acts as a single SQL engine that can query and join data from among several other systems, and it accelerates those queries using Apache Arrow. So it is a combo of (Drill + Arrow): schema-free SQL for variety of data sources plus a columnar in-memory analytics execution engine.
Dremio believes that BI today involves too many layers. Source systems, via ETL processes, feed into data warehouses, which may then feed into OLAP cubes. BI tools themselves may add another layer, building their own in-memory models in order to accelerate query performance. Dremio thinks that’s a huge mess and disintermediates things by providing a direct bridge between BI tools and the source system they’re querying. The BI tools connect to Dremio as if it were a primary data source, and query it via SQL. Dremio then delegates the query work to the true back-end systems through push-down queries that it issues. Dremio can connect to relational databases (DB2, Oracle, SQL Server, MySQL, PostgreSQL), NoSQL stores (MongoDB, Amazon Redshift, HBase, MapR-FS), Hadoop, cloud blob stores like S3, and ElasticSearch.
Here’s how it works: all data pulled from the back-end data sources is represented in memory using Arrow. Combined with vectorized (in-CPU parallel processing) querying, this design can yield up to a 5x performance improvement over conventional systems (company claims). But a perhaps even more important optimization is Dremio’s use of what it calls “Reflections,” which are materialized data structures that optimize Dremio’s row and aggregation operations. Reflections are sorted, partitioned, and indexed, stored as files on Parquet disk, and handled in-memory as Arrow-formatted columnar data. This sounds similar to ROLAP aggregation tables).
Andrew Brust from ZDNet said, “While Dremio’s approach to this is novel, and may break a performance barrier that heretofore has not been well-addressed, the company is nonetheless entering a very crowded space. The product will need to work on a fairly plug-and-play basis and live up to its performance promises, not to mention build a real community and ecosystem. These are areas where Apache Drill has had only limited success. Dremio will have to have a bigger hammer, not just an Arrow”.