Register UDFs

A UDF must be registered in the database before the function can be recognized and used by SQL.

• Example: Exponentiation
  In this example, suppose you have written an external UDF to perform exponentiation of floating point values, and want to register it in the MATH schema.
• Example: String search
  Suppose you have written a UDF to look for the existence of a given short string, passed as an argument, within a given CLOB value that is also passed as an argument. The UDF returns the position of the string within the CLOB if it finds the string, or zero if it does not.
• Example: BLOB string search
  In this example, you want the FINDSTRING function to work on BLOBs as well as on CLOBs. To do this, you define another FINDSTRING taking BLOB as the first parameter:
• Example: String search over UDT
  Assume that you are satisfied with the FINDSTRING functions from the BLOB string search, but now you have defined a distinct type BOAT with source type BLOB.
• Example: AVG over a UDT
  This example implements the AVG column function over the CANADIAN_DOLLAR distinct type.
• Example: Counting
  Your simple counting function returns a 1 the first time and increments the result by one each time it is called. This function takes no SQL arguments, and by definition it is a NOT DETERMINISTIC function since its answer varies from call to call.
• Example: Table function returning document IDs
  In this example, you have written a table function that returns a row consisting of a single document identifier column for each known document in your text management system that matches a given subject area (the first parameter) and contains the given string (second parameter).