Tuesday, June 26, 2007
The Oracle10g external table feature
The Oracle10g external table feature, which allows external data, such as flat files, to be exposed within the database just like a regular database table. External tables can be accessed by SQL, so that external files can be queried directly and in parallel using the full power of SQL, PL/SQL, and Java. External tables are often used in the Extraction, Transformation, and Loading (ETL) process to combine data-transformations (through SQL) with data-loading into a single step. External tables are a very powerful feature with many possible applications in ETL and other database environments where flat files are processed; it is an alternative to using SQL*Loader.