Chapter 8 - SQL/OLB and SQL/JRT

Abstract

The three technologies that were developed by the SQLJ Group involve embedding Structured Query Language (SQL) static statements in Java programs, invoking Java methods from SQL statements, and defining SQL structured user-defined types that are actually Java classes used from within the database. The very earliest work of the SQLJ Group used technology contributed by Oracle, including an implementation of a translator that accepted Java programs containing embedded SQL statements, and produced corresponding Java programs that used the JDBC interface for execution of those SQL statements. A new part of the SQL: 1999 standard offers an arrangement that resolves most of the difficulties posed by writing programs using JDBC while retaining all of its benefits. This new part of the SQL standard, known as SQL/OLB (Object Language Bindings) provides a way to write Java programs in which one can embed SQL statements similarly to the embedded SQL capabilities provided for other programming languages. SQL/JRT places additional restrictions on the Ordering clause of user defined types that were not placed by the National Committee for Information Technology Standards (NCITS) 331.2.