Teradata Parallel Data Pump

Chapter 5: Using INMOD and Notify Exit Routines
Using INMOD and Notify Exit Routines
Using INMOD and Notify Exit Routines
This section provides some specific information required for using INPUT and notify exit
routines in Teradata TPump. Topics include Teradata TPump-specific restrictions, the
Teradata TPump/INMOD interface for different client operating systems, preparation of the
INMOD program, INMOD input values, INMOD output values, and programming
specifications for Unix-based and Windows clients.
Teradata TPump-specific Restrictions
INMOD names should be unique within the system. INMODs are not re-entrant and cannot
be shared by two Teradata TPump (or FastLoad, MultiLoad, or FastExport) sessions at the
same time.
Some changes have been made to the INMOD utility interface for Teradata TPump because of
operational differences between Teradata TPump and the older utilities. For compatibility
with INMODs, the FDLINMOD parameter should be used. The use of this parm provides
support of existing INMODs, with the following restrictions:
• When the FDLINMOD parm is used, INMODs that are compatible with other utilities
may be used. However, if a range of records is requested from an FDL-compatible INMOD
(using FROM, FOR, or THRU on the IMPORT command), Teradata TPump bypasses any
default record checkpointing. If there is a recovery under these circumstances, Teradata
TPump starts over and acquires the records again from the beginning of the range. Under
these same circumstances, if checkpointing is requested by specifying the CHECKPOINT
parameter on the BEGIN LOAD command, Teradata TPump terminates with an error.
• If a range of records is not requested when using an FDL-compatible INMOD, Teradata
TPump performs checkpointing, either by default or by the user’s request. If there is a
recovery and the INMOD supports recovery, Teradata TPump continues its data
acquisition from the last recorded checkpoint. However, the source sequence numbers
generated by Teradata TPump may not correctly identify the sequence in which the
INMOD supplied the records. Despite this discrepancy, the data is still applied correctly.
• An FDL-compatible INMOD routine cannot be specified in conjunction with the INFILE
specification of a Teradata TPump IMPORT command. If an INMOD is specified together
with the INFILE specification, Teradata TPump performs the file read operation and the
INMOD acts as a pass-through filter. Since an FDL-compatible INMOD always performs
the file read operation, it is not valid with a Teradata TPump INFILE specification.
Warning:
The Teradata TPump default is to take a checkpoint every 15 minutes. With other loading
utilities, checkpointing must be explicitly requested. If an attempt to run with an INMOD that
does not use checkpointing is made, problems may arise when Teradata TPump defaults to a
checkpoint mode. To avoid this condition, Teradata TPump checkpointing by specifying zero
can be disabled as the checkpoint rate parameter on the BEGIN LOAD command, so that the
checkpoint is never reached. This may be imperative for users who do not have INMODs capable
of checkpointing.
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