The full name of a DB2 function is: schema-name.function-name, where schema-name is an identifier that provides a logical grouping for the SQL objects. The schema name for XML Extender UDFs is DB2XML. The DB2XML schema name is also the qualifier for the XML Extender UDTs. In this book, references are made only to the function name.
The function path is an ordered list of schema names. DB2 uses the order of schema names in the list to resolve references to functions and UDTs. You can specify the function path by specifying the SQL statement SET CURRENT FUNCTION PATH. This sets the function path in the CURRENT FUNCTION PATH special register.
For the XML Extender, it is a good idea to add the db2xml schema to the function path. This allows you to enter XML Extender UDF and UDT names without having to prefix them with db2xml. The following example shows how to add the db2xml schema to the function path:
SET CURRENT FUNCTION PATH = db2xml, CURRENT FUNCTION PATH
Important: Do not add db2xml as the first schema in the function path if you log on as db2xml; db2xml is automatically set as the first schema when you log on as db2xml. This generates an error condition because your function path will begin with two db2xml schemas.