How the CESSDA Euro Question Bank integrates with different technologies

The CESSDA Euro Question Bank (EQB) project provides a central search facility across all CESSDA’s survey questions in different languages, as shown at EDDI last year. It uses a metadata schema based on DDI-Lifecycle standard and also provides conversion mappings from DDI-Codebook. The latest work in EQB was to finalize this metadata schema in close collaboration with the CESSDA CMM2 project and is now one of the major project results. It combines an object structure that is not too complicated with properties that are compatible to the DDI schema. Using this metadata schema, CESSDA service providers can supply their contents from various formats to EQB.

The EQB system architecture consists of the EQB-Frontend, implemented with the Vaadin user interface technology, and the EQB-Backend, using Elasticsearch for the search index and the FlatDB relational database on MySQL to store DDI snippets. In addition, EQB uses a challenging technology called Docker. Docker is an operating system virtualization tool to manage, centralize, ease and deploy heterogeneous applications and services. The presentation will show the different components of the EQB application, focusing on new developments during the last year and implementation issues with the DDI metadata used.