Home
Extending Informix®Beyond standard relational database objects, HCL Informix® can be extended to handle specialized data types, access methods, routines, and other objects. Informix® includes many built-in extensions that are fully integrated in the database server. Informix® also provides DataBlade® modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for Informix®.
Creating extensionsYou can create user-defined data types, routines, access methods, and other database objects to suit your needs. You can use application programming interfaces to write user-defined routines and applications that access data in Informix® databases.
R-Tree Index User's GuideThe Informix® R-Tree Index User's Guide describes the HCL Informix® R-tree secondary access method and how to access and use its components.
Develop DataBlade® modules that use the R-tree secondary access method
Design a user-defined data type
Implementing data type hierarchy
Union support function in a data type hierarchy

Union support function in a data type hierarchy

When you create the Union support function, you must create separate SQL functions for each indexable column type. For example, you must create the following SQL Union functions:

Union (MyPoint, MyPoint, MyPoint)
Union (MyBox, MyBox, MyBox)
Union (MyCircle, MyCircle, MyCircle)
Union (MyShape, MyShape, MyShape)

All these Union support functions, however, can be mapped to the same C code. Similar to strategy functions, the internal C code that the Union functions map to first checks to see what actual data type it is operating on (either MyPoint, MyBox, or MyCircle) and then calls the appropriate code for that data type. For example, if the function call is Union (MyCircle, MyCircle, MyCircle), it executes the appropriate code for the union of two MyCircle data types.

The preceding discussion is true only for the Union support function and not for the other support functions.

Rate this topic

5 stars 4 stars 3 stars 2 stars 1 star

Comment on this topic.

By clicking this box, you acknowledge that you are NOT a U.S. Federal Government employee or agency, nor are you submitting information with respect to or on behalf of one. HCL provides software and services to U.S. Federal Government customers through its partners immixGroup, Inc. Contact this team at https://hcltechsw.com/resources/us-government-contact. Do not include any personal data in this Comment box.