Purpose:

Describe the successful phased approach to Unicode support implemented for the Teradata very large database engine and the current status of internationalization support.

Description:

About five years ago, the decision was made to modify the Teradata massively parallel database engine to support the Unicode character set. At that time, the database engine code consisted of millions of lines of code, much of it assuming particular representations of character data. It was clear that this was no easy task. In order to avoid a resource and risk bottleneck that would have been infeasible for a single release, a phased approach was employed.

The phased approach started with strictly internal Unicode support. The immediate benefit was the ability to interchange Japanese data between clients with different encodings for Japanese. The next phase constructed a method for defining external single byte characters, allowing appropriate character support for almost every nation in the world. The latest phase externalizes the Unicode support, finally allowing the user to input and output Unicode data directly, without relying on legacy character sets. The last bastions of non- Unicode areas in the DBS code are falling, with improved support for handling all forms of localized data.

Conclusion:

A phased approach to Unicode support within a large existing application offers an attractive alternative to a potentially overwhelming attempt to offer full support within the span of a single release. Teradata Unicode support is finally directly accessible to the user.