What it Does
When Teradata MultiLoad is invoked, the utility executes the Teradata MultiLoad commands and Teradata SQL statements in the Teradata MultiLoad job script.
Table 1 describes the phases of Teradata MultiLoad operations.
Phase |
Teradata MultiLoad Operation |
Preliminary |
1 Parses and validates all of the Teradata MultiLoad commands and Teradata SQL statements in a Teradata MultiLoad job 2 Establishes sessions and process control with Teradata Database 3 Submits special Teradata SQL requests to Teradata Database 4 Creates and protects temporary work tables and error tables in Teradata Database |
DML Transaction |
Submits the DML statements specifying the insert, update, and delete tasks to Teradata Database |
Acquisition |
1 Imports data from the specified input data source 2 Evaluates each record according to specified application conditions 3 Loads the selected records into the worktables in Teradata Database (There is no acquisition phase activity for a Teradata MultiLoad delete task.) |
Application |
1 Acquires locks on the specified target tables and views in Teradata Database 2 For an import task, inserts the data from the temporary work tables into the target tables or views in Teradata Database 3 For a delete task, deletes the specified rows from the target table in Teradata Database 4 Updates the error tables associated with each Teradata MultiLoad task |
Cleanup |
1 Forces an automatic restart/rebuild if an AMP went offline and came back online during the application phase 2 Releases all locks on the target tables and views 3 Drops the temporary work tables and all empty error tables from Teradata Database 4 Reports the transaction statistics associated with the import and delete tasks |