16.20 - Teradata Commands for UDF Debugging - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL External Routine Programming

Advanced SQL Engine
Teradata Database
Release Number
Release Date
April 2020
Content Type
Programming Reference
Publication ID
English (United States)
The following Teradata-specific commands are available only to GDB with the Teradata C/C++ UDF Debugger extensions:

Some of these commands use thread selectors as parameters or in their output. A thread selector consists of three numeric values separated by a slash (/) character. Thread selectors take the form node/process/thread, where node is the number of the vproc that invoked the UDF, and process and thread are the identifiers assigned by the operating system to the process and thread that executes the UDF. Together the node and thread uniquely identify every task on the system, so process is normally omitted. For example, a thread selector for a PE thread might be 16383//7137; 0//22638 could be an AMP thread.

Thread selectors in UDF debugging sessions typically correspond to UDFs being debugged. However, udfsectsk processes that execute the UDFs have threads in addition to the one that executes the UDF. The debugger normally hides those threads but they become visible if they hit a breakpoint, watch point, or a signal that the debugger catches. When that happens, those threads are handled the same as UDF threads and are assigned thread selectors.