External-language routines

An external-language routine is a user-defined routine (UDR) that is written in an external language. The body of an external-language routine contains statements for operations such as flow control and looping, as well as special HCL Informix® library calls to access the database server. Therefore, you must use the appropriate compilation tool to parse and compile an external-language routine into an executable format.

The database server supports UDRs written in C and in Java™.

Routines in C
To execute SQL statements in C UDRs, you must use the DataBlade API. You cannot use ESQL/C in C UDRs.

To write routines in C, you need a C compiler. For information about how to write UDRs in C, refer to the HCL Informix DataBlade API Programmer's Guide and the IBM Informix DataBlade API Function Reference.
Routines in Java
To write Java routines, you need a Java development kit to compile your Java routines.

For information about how to write Java UDRs, refer to the HCL J/Foundation Developer's Guide.

Important: It is recommended that you use the DBDK to develop UDRs in external languages because the DBDK enforces standards that facilitate migration between different versions of the database server.