16.10 - Deleting the Fallback Data File - Access Module

Teradata Tools and Utilities Access Module Reference

prodname
Access Module
vrm_release
16.10
created_date
July 2017
category
Programming Reference
featnum
B035-2425-077K

By default, the Teradata Access Module for Named Pipes reports an end-of-file condition and deletes the fallback data file when the last record written to the pipe is read and sent to the reader process. But because the module handles only raw data streams and disregards data formats imposed by the writer or reader processes, it cannot distinguish between a normal end-of-file condition and an end-of-data condition that would occur if the writer process halts prematurely.

If the writer process terminates before achieving a normal end-of-file condition, the Teradata Access Module for Named Pipes, by default, interprets the empty pipe as a normal end-of-file condition and deletes the fallback data file. In this case, the data would no longer be available to support a subsequent reader process restart operation.

When confirm_fallback_deletion flag is not set to "Y", the fallback file can be preserved in cases where the client utility is terminating prematurely (due to a DBS error, for example) by setting the Data connector attribute PM_ATR_NAME_KEEP_RESTART_RESOURCES with a value of PM_ATR_VALU_YES.