Manejadores de bases de datos activas tradicionales como Starburst, Oracle, DB2 y Stalog hicieron uso de triggers de proposito general basado en el estandar de SQL3
Kline, Kline, and Hunt present an updated resource text for programmers, developers, and database administrators describing the latest ANSI standard, SQL 2003 (SQL3
) version of each SQL command, and then documenting how those commands are implemented in Microsoft SQL Server 2008, Oracle 11g, MySQL 5.1, and PostgreSQL 8.3.
La parte del nucleo de Mineria de Datos es responsabilidad de un procedimiento no-SQL, llamado core operator el cual recibe los datos recuperados por el SQL server, extrae las reglas y las retorna en forma de una relacion SQL3
hacia el SGBD.
It is straightforward to adapt these definitions to different representations, for example, a representation that is based on the PERIOD data type of the evolving SQL/Temporal part of the SQL3
Many organizations support the development of SQL3
, an enhanced structured query language (SQL) that addresses some object oriented database concepts, although efforts to define a specification for this standard are moving rather slowly.
For example, the current SQL3
proposals  permit such things as "nonsquare squares" (i.e., values of type SQUARE whose sides are of different lengths), with the result that SQL3
can hardly be regarded as a good "model of reality." In fact, those SQL3
proposals do not allow type constraints, such as the constraint that values of type SQUARE must have sides of equal length, even to be stated, much less enforced [5, 6].
They also have been integrated as part of the SQL3
standard [Melton 1994; 1996] currently under development.
The relational language for the next-generation SQL, SQL3
, currently provides an operation called recursive union that supports recursive processing of tables (Melton 1996).
We chose OQL because even though it is a small language, and hence easier to comprehend, it contains most of the language features that are showing up in other object query languages and proposed relational extensions such as SQL3
[Beech 1993], now called SQL:1999 [Eisenberg and Melton 1999].
While it has many appealing features, it lacks some of the power inherent in database query languages, such as SQL3
. Therefore, we are attempting a convergence of Z39.50 and SQL3
, which we dub ZQL.