HandsOn DB: Managing Data Dependencies Involving Human Actions

Mohamed Eltabakh, Walid Aref, Ahmed Elmagarmid, Mourad Ouzzani

Research output: Contribution to journalArticle

1 Citation (Scopus)


Consider two values, x and y, in the database, where y = F(x). To maintain the consistency of the data, whenever x changes, F needs to be executed to re-compute y and update its value in the database. This is straightforward in the case where F can be executed by the DBMS, e.g., SQL or C function. In this paper, we address the more challenging case where F is a human action, e.g., conducting a wet-lab experiment, taking manual measurements, or collecting instrument readings. In this case, when x changes, y remains invalid (inconsistent with the current value of x) until the human action involved in the derivation is performed and its output result is reflected into the database. Many application domains, e.g., scientific applications in biology, chemistry, and physics, contain multiple such derivations and dependencies that involve human actions. In this paper, we propose HandsOn DB, a prototype database engine for managing dependencies that involve human actions while maintaining the consistency of the derived data. HandsOn DB includes the following features: (1) semantics and syntax for interfaces through which users can register human activities into the database and express the dependencies among the data items on these activities; (2) mechanisms for invalidating and revalidating the derived data; and (3) new operator semantics that alert users when the returned query results contain potentially invalid data, and enable evaluating queries on either valid data only, or both valid and potentially invalid data. Performance results are presented that study the overheads associated with these features and demonstrate the feasibility and practicality in realizing HandsOn DB.

Original languageEnglish
Article number6560053
Pages (from-to)2193-2206
Number of pages14
JournalIEEE Transactions on Knowledge and Data Engineering
Issue number9
Publication statusPublished - 1 Sep 2014



  • Data dependencies
  • Database design
  • manipulation languages
  • modeling and management
  • Query design and implementation languages
  • Query processing

ASJC Scopus subject areas

  • Computational Theory and Mathematics
  • Information Systems
  • Computer Science Applications

Cite this