A web application that allows to formulate complex queries against big databases. The query concepts are drag-and-dropped to form logical connections. Results can be further restricted by filters and date range.

Open project website
Challenge image


How would you compose queries against a database in a visual, interactive way? What if all parts of the query are available as "concepts", organized in a tree structure? The team at bakdata asked me to build a hand-tailored single page web app, which would rely heavily on drag and drop to compose queries and to execute them against an API backend.

Solution image


Introducing: conquery. Using conquery, item trees can be explored, similar to your file system. The so called "concepts" in the tree vary in their degree of abstraction. This allows a user to ask queries in a very abstract manner, but also in great detail. To build a query, the concepts are dropped into a query editor, using AND/OR-connections. Results can be downloaded as a CSV file.

My role image

My role

Over the course of 9 months, I worked part-time on the UX and React frontend, while my colleague Manuel crafted the Java backend. The clear responsibilities allowed us to iterate the feature set quickly. After I had started working full-time at neXenio, newly hired developers at bakdata continued improving the web app. Eventually, thanks to bakdata's engagement, it was possible to open source the frontend code.

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