In recent years a small number of web-based tools have been proposed to help students learn to write SQL query statements and also to assess students’ SQL writing skills. SQLify ...
A set of mutation operators for SQL queries that retrieve information from a database is developed and tested against a set of queries drawn from the NIST SQL Conformance Test Sui...
SPARQL currently does not include any form of nested queries. In this paper we present a proposal to incorporate nested queries into SPARQL along the design philosophy of SQL neste...
Date's popular critique of SQL's three-valued logic [4, 3] purports to demonstrate that SQL queries can produce erroneous results when nulls are present in the database....
In this paper, we study a simple SQL extension that enables query writers to explicitly limit the cardinality of a query result. We examine its impact on the query optimization an...