Understanding SQL built-in functions

 

Ever since the advent of relational databases and the SQL language, database vendors have been at odds with the concept of standardization.  Every database vendor desires to be ANSI compliant with regard to their relational database and the structure of their SQL, but vendors also have a proprietary interest in extending the functionality of their database so that they can be better than their competition.

 

This market reality has led to the development of SQL extensions.  Within the Oracle9i database, these SQL extensions are called built-in functions, or BIFs.  Oracle BIFs have been introduced to extend the functionality of SQL, provide date arithmetic functions, and also allow for the creation of customized functions within SQL statements.

 

Oracle has introduced over 50 different built-in functions into their database engine, and many of these powerful functions allow for automatic data transformation inside the SQL query.

 

Here is a link to a list of Oracle BIFs –

 http://download-west.oracle.com/otndoc/oracle9i/901_doc/server.901/a90125/functions2.htm#80856