How schema independent are schema free query interfaces?

— Real-world databases often have extremely complex schemas. With thousands of entity types and relationships, each with a hundred or so attributes, it is extremely difficult for new users to explore the data and formulate queries. Schema free query interfaces (SFQIs) address this problem by allowing users with no knowledge of the schema to submit queries. We postulate that SFQIs should deliver the same answers when given alternative but equivalent schemas for the same underlying information. In this paper, we introduce and formally define design independence, which captures this property for SFQIs. We establish a theoretical framework to measure the amount of design independence provided by an SFQI. We show that most current SFQIs provide a very limited degree of design independence. We also show that SFQIs based on the statistical properties of data can provide design independence when the changes in the schema do not introduce or remove redundancy in the data. We propose a novel...

• Type: Journal
• Year: 2011
• Where: ICDE
• Authors: Arash Termehchy, Marianne Winslett, Yodsawalai Chodpathumwan
• Keywords: Current Sfqi, Database, Design Independence, ICDE 2011, Schema Free Query