SEQUEL or SQL

SQL’s purpose is to provide an interface to a relational database such as Oracle Database. Dr. Edgar Frank “Ted” Codd introduced the first commercially available implementation of SQL. Today, SQL is accepted as the standard RDBMS language. The features of SQL include processing sets of data as groups rather than as individual units and providing automatic navigation to the data. It uses statements that are complex and powerful individually, and that therefore stand alone. Flow-control statements were not part of SQL originally, but they are found in the recently accepted optional part of SQL. Flow-control statements are commonly known as “persistent stored modules” (PSM), and the PL/SQL extension to Oracle SQL is similar to PSM. Major commercial database developers have set a trend of offering “Express” versions of their databases. Companies such as Microsoft, Oracle and IBM DB2 are a part of this trend setting. Microsoft has a program called SQL Express which has the following features; SQL Server Configuration Manager, Replication, Advanced Query Optimizer, SMO/RMO, Sqlcmd, and Integration with Visual Studio 2005.

SQL Express all has snapshot isolation level features, Native XML support, SQL language support-Multiple Active Result Sets (MARS), and Dedicated Admin Connection-Import/Export Wizard. These features are different than that of Oracles express version. Some of the software limitations include a 1GB maximum memory, the maximum size of each relational database. Oracle Express is Oracle’s express edition of their SQL database. This edition has many different features that can be used. Some of those features include; Interactive reports, Declarative BLOB support, Enhanced report printing, adding to the theme repository, Optional runtime-only installation, improved security, Application date format, and Application builder refinements. These features are used to create statements and define the language that Oracle databases use. These types of features are also present in the express edition of SQL that IBM created. Oracle Express is limited by the fact that it can run only one instance of Oracle Database on each individual computer, unless upgraded. IBM DB2 offers software called DB2 Express which is their express edition of their SQL software.