Data Consistency: Toward a Terminological Clarification

Abstract. ‘Consistency ’ is an ubiquitous term in data engineering. Its relevance to quality is obvious, since ‘consistency ’ is a commonplace di-mension of data quality. However, connotations are vague or ambiguous. In this paper, we address semantic consistency, transaction consistency, replication consistency, eventual consistency and the new notion of par-tial consistency in databases. We characterize their distinguishing prop-erties, and also address their differences, interactions and interdepen-dencies. Partial consistency is an entry door to living with inconsistency, which is an ineluctable necessity in the age of big data.