COACT: a query interface language for collaborative databases

Khaleel Mershad, Qutaibah M. Malluhi, Mourad Ouzzani, Mingjie Tang, Michael Gribskov, Walid G. Aref, Deo Prakash

Research output: Contribution to journalArticle


Data curation activities in collaborative databases mandate that collaborators interact until they converge and agree on the content of their data. In a previous work, we presented a cloud-based collaborative database system that promotes and enables collaboration and data curation scenarios. Our system classifies different versions of a data item to either pending, approved, or rejected. The approval or rejection of a certain version is done by the database Principle Investigators (or PIs) based on its value. Our system also allows collaborators to view the status of each version and help PIs take decisions by providing feedback based on their experiments and/or opinions. Most importantly, our system provided mechanisms for history tracking of different versions to trace the modifications and approval/rejection done by both collaborators and PIs on different versions of a data item. We labeled our system as Update-Pending-Approval model (or UPA). In this paper, we describe a high level SQL query interface language for PIs and collaborators to interact with the UPA framework. We define a set of UPA keywords that are used as a part of the history tracking mechanism to select specific versions of a data item, and a set of UPA options that select specific versions based on possible future decisions of PIs. We implemented our query interface mechanism on top of Apache Phoenix, taking into consideration that the UPA system was implemented on top of Apache HBase. We test the performance of the UPA query language by executing several queries that contain different complexity levels and discuss their results.

Original languageEnglish
Pages (from-to)121-151
Number of pages31
JournalDistributed and Parallel Databases
Issue number1
Publication statusPublished - 1 Mar 2018



  • Collaborative databases
  • False positives and negatives
  • Query options
  • SQL
  • True values
  • Update authorization

ASJC Scopus subject areas

  • Software
  • Information Systems
  • Hardware and Architecture
  • Information Systems and Management

Cite this

Mershad, K., Malluhi, Q. M., Ouzzani, M., Tang, M., Gribskov, M., Aref, W. G., & Prakash, D. (2018). COACT: a query interface language for collaborative databases. Distributed and Parallel Databases, 36(1), 121-151.