Missing UDF Returns an Error

An attempt to execute a UDF that does not exist on the server returns an error.

If you attempt to execute a query similar to:

select my_sum1(n_tabkey) from tabudf()

where:

tabudf() is a table UDF, and
the UDF my_sum1() does not exist on the server,

this error is returned:

Could not execute statement.
External procedures or functions are not allowed across server types.
SQLCODE=-1579, ODBC 3 State="HY000"
Line 1, column 1