Niko's Project Corner

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Benchmarking Elasticsearch and MS SQL on NYC Taxis

(7th May 2017)

The NYC Taxi dataset has been used on quite many bench­marks (for ex­am­ple by Mark Litwintschik), per­haps be­cause it has a quite rich set of columns but their mean­ing is mostly triv­ial to un­der­stand. I de­vel­oped a Clo­jure pro­ject which gen­er­ates Elas­tic­search and SQL queries with three dif­fer­ent tem­plates for fil­ters and four dif­fer­ent tem­plates of ag­gre­ga­tions. This should give a de­cent in­di­ca­tion of these databases per­for­mance un­der a typ­ical work­load, al­though this test did not run queries con­cur­rently and it does not mix dif­fer­ent query types when the bench­mark is run­ning. How­ever bench­marks are al­ways tricky to de­sign and ex­ecute prop­erly so I'm sure there is room for im­prove­ments. In this pro­ject the tested database en­gi­nes were Elas­tic­search 5.2.2 (with Or­acle JVM 1.8.0_121) and MS SQL Server 2014.

Languages: Clojure
Tags: GitHub Databases Elasticsearch SQL
GitHub: nikonyrh/nyc-taxi-data

Efficient in-memory analytical database

(1st December 2013)

Tra­di­tional databases such as MySQL are not de­signed to per­form well in an­alyt­ical queries, which re­quires ac­cess to pos­si­bly all of the rows on se­lected columns. This re­sults in a full table scan and it can­not ben­efit from any in­dexes. Column-ori­ented en­gi­nes try to cir­cum­vent this is­sue, but I went one step deeper and made the stor­age column value ori­ented, sim­ilar to an in­verted in­dex. This re­sults in 2 — 10× speedup from op­ti­mized colum­nar so­lu­tions and 80× the speed of MySQL.

Languages: C++
Tags: FastCGI SQL Databases