Teradata custom restart
allows a step to be restarted where the load stopped rather than being
started from the beginning of the step. Teradata custom restart is
available when loading from a SAS or other DBMS source that is not
on the same server as the Teradata target. Custom restart is not available
when Upsert is selected.
When custom restart
is supported, the step determines the last good checkpoint, and the
row number is saved as the restart number. After the error condition
is fixed by an administrator (for example, the database size has been
extended), the next run of that job will start loading the target
table where it stopped.
The load styles that
are available on the Teradata loader for SAS to Teradata loads are:
-
-
Determine load technique
at runtime (Multiload/Fastload)
-
-
-
Trickle Feed Append
(TPUMP)
-
Upsert (Multiload/Upsert)
When restart is used, and when the
Determine
load technique at runtime option is selected, the same
technique that was used in the first run is used during the restart.
Using the
Use
TPT Utilities option with the
Determine load
technique at runtime option provides a more seamless
restart because Fastload without TPT does not support restart through
the access engine, which calls the TPUMP functionality multistatement.
Other TPT and load style combinations result in the following manner:
-
When TPT is set, Multiload will
generate CHECKPOINT=xxx.
-
When TPT is not set, Multiload
will generate ML_CHECKPOINT=xxx.
-
Regardless of the TPT setting,
CHECKPOINT=xxx will be generated when Fastload is used.
The
Use
TPT Utilities check box is located on the
Load
Technique tab of the Teradata Table Loader's properties
window. This check box is available if the source table is not in
the same Teradata database as the target table and if one of the load
styles for the Teradata loader, except
Upsert (Multiload/Upsert),
is selected. When this check box is selected, SAS Data Integration
Studio uses the Teradata parallel transporter (TPT) API for loading
data. You can select additional TPT options in the
TPT window
located on the
Teradata Options tab on the
Table
Options tab in the Teradata Table Loader properties window.