OPAQUE data types

Opaque User Defined Types can be implemented in IBM^® Informix^® with the CREATE OPAQUE TYPE statement. The storage structure of an OPAQUE type is unknown to the database server, data can only be accessed through user-defined routines.

Genero BDL does not support the IBM Informix OPAQUE data types:

• It is not possible to define BDL variables with an opaque type.
• The static SQL syntax does not support OPAQUE-related syntax elements:
  • The DDL statements CREATE OPAQUE TYPE, DROP TYPE, CREATE CAST and DROP CAST are not allowed,
  • In CREATE TABLE / ALTER TABLE DDL statements, the data type must be a built-in type.
  • The :: cast operator is not supported. However, the CAST() expressions are allowed.
• The fgldbsch schema extractor will report an invalid data type if you try to get the schema for a table with a column defined with a OPAQUE type.