Genero BDL supports the STRING data type in addition to CHAR and VARCHAR. While the STRING data type is useful in certain situations, there are times when you should use CHAR or VARCHAR instead.

Genero Business Development Language (BDL) introduces a new data type named STRING, which is similar to VARCHAR but without a size limit. The STRING data type does not exist in IBM® Informix® 4GL. The STRING data type implementation is optimized for memory usage; unlike CHAR/VARCHAR, BDL will only allocate the memory needed to hold the actual character string value in a STRING variable.

A STRING variable is typically used within utility functions (for example, to hold the path to a file). Another typical usage is with CONSTRUCT, to hold the SQL condition. The STRING variable can then be completed to build the SQL text and passed to the PREPARE or DECLARE instruction.

STRING variables can be used in SQL statements. However, it is recommended to use the CHAR/VARCHAR variables that match the size of the corresponding CHAR/VARCHAR database columns.

The STRING data type has a number of built-in methods that are very useful and will reduce source code, such as getLength().