OQL

Object query language

OQL was developed to play the role of SQL for Object-Oriented Databases, especially those adhering to the ODMG Standard [4] where the language is defined. Unlike SQL, OQL is a functional language, and its operators can be composed to an arbitrary level of nesting within a query provided the query remains type-correct. Fegaras and Maier [8] have shown how OQL expressions have a direct translation into monoid Comprehensions.

Optimisation techniques for OQL that exploit its inherent functional nature are discussed in [5, 6, 8]. OQL has been influential in the development of the SQL3 standard and also the functional core of the XQuery language for XML. Thus optimisation techniques developed for OQL are also applicable to these languages.

The fundamental modelling concept of object identifiersfor entity instances was accepted into the database mainstream in the late 1980s, and the move to using SQL-like syntax for querying such data...

Authors and Affiliations

1. University of Aberdeen, Aberdeen, UK

   Peter M. D. Gray

Corresponding author

Correspondence to Peter M. D. Gray .

Editors and Affiliations

1. Georgia Institute of Technology College of Computing, Atlanta, GA, USA

   Ling Liu

2. University of Waterloo School of Computer Science, Waterloo, ON, Canada

   M. Tamer Özsu

1. Department of Information Technology, Uppsala University, Uppsala, Sweden

   Tore Risch

Reprints and permissions

© 2018 Springer Science+Business Media, LLC, part of Springer Nature

Policies and ethics