A relational database model and prototype for storing diverse discrete linguistic data

This article describes a model for storing multiple forms of linguistic data within a relational database as developed and tested through a prototype database for storing data from Arabic dialects. A challenge that typically confronts linguistic documentation projects is the need for a flexible data model that can be adapted to the growing needs of a project (Dimitriadis, 2006). Contributors to linguistic databases typically cannot predict exactly which attributes of their data they will need to store, and therefore the initial design of the database may need to change over time. Many projects take advantage of the flexibility of XML and RDF to allow for continuing revisions to the data model. For some projects, there may be a compelling need to use a relational database system, though some approaches to relational database design may not flexible enough to allow for adaptation over time (Dimitriadis, 2006). The goal of this article is to describe a relational database model which can adapt easily to storing new data types as a project evolves. It both describes a general data model and shows its implementation within a working project. The model is primarily intended for storing discrete linguistic elements (phonemes, morphemes including general lexical data, sentences) as opposed to text corpora, and would be expected to store data on the order of thousands to hundreds of thousands of rows.1 The relational model described in this paper is centered around the linguistic datum, encoded as a string of characters, associated in a many-to-many relationship with ‘tags,’ and in many-to-many named relationships with other datums.2 For this reason, the model will be referred to as the ‘tag-and-relationship’ model. The combination of tags and relationships allows the database to store a wide variety of linguistic data. This data model was developed in tandem with a project to encode linguistic data from Arabic dialects (the “Database of Arabic Dialects”, DAD).3 Arabic is an extremely diverse language group, with a dialects stretching from Mauritania to Afghanistan,