Java Development Resources

Hibernate Dialect For Virtuoso

Q: Hibernate uses vendor-specific dialect classes that abstract away the specific flavor of SQL for that database vendor. For example, it may abstract away the manner in which a specific DBMS manages dates and times through a TIMESTAMP type with casting functions. When you set up Hibernate, you specify which SQL dialect to use, but there is none specific to Virtuoso or OpenLink. Which should be used?

A: Virtuoso is an ANSI SQL (89, 92, 99/SQL3) compliant engine and as such we would expect Hibernate to have Standard ANSI SQL Dialect that can be used. However, this appears not to be the case. All dialects appear to be mapped to individual vendors and not standards. Ideally, Hibernate should use the available metadata calls to deduce information about the DBMS's underlying SQL engine behavior. Barring that, OpenLink suggests that you use the SQL Server dialect as that is closest to Virtuoso and seek to extend the dialect where necessary.