Drop Work Table

1. Purpose of the Task:
• The Drop Work Table task is responsible for dropping (deleting) the loading table once the data loading process is complete. This helps in cleaning up the temporary resources used during the data integration process.
2. When is the "Drop Work Table" Task Executed?:
• This task is executed after the data loading phase, once the data has been successfully moved into the staging area or is no longer required.
• The task runs if the DELETE_TEMPORARY_OBJECTS option is selected in the Knowledge Module (KM) configuration. This option ensures that the loading table is dropped to free up resources.
• If the DELETE_TEMPORARY_OBJECTS option is not selected, the loading table will not be dropped, and it may be preserved for debugging purposes.
3. Execution of the Command:
• The task uses the following command to drop the loading table:

4.  drop table <%=snpRef.getTable("L", "COLL_NAME", "A")%>

• Explanation:
• <%=snpRef.getTable("L", "COLL_NAME", "A")%>: This is a dynamic expression generated by the ODI (Oracle Data Integrator) system, which retrieves the name of the loading table to be dropped.
• "L": Represents the type of object, in this case, a loading table.
• "COLL_NAME": Represents the name of the loading table (this will be replaced with the actual table name during execution).
• "A": Represents a specific alias or schema, if applicable.
4. Command Behavior:
• The drop table command will execute regardless of whether the table exists or not. This is facilitated by having the Ignore Errors flag activated, which prevents the task from failing if the table does not exist.
• The table is dropped from the target database, which is typically the staging area in this case.
5. Impact:
• Dropping the loading table helps with resource cleanup, ensuring that the temporary tables used during the loading process are removed after they are no longer needed.
• If the table is dropped successfully, it ensures that the system does not retain unnecessary temporary objects.

Summary of Steps in the "Drop Work Table" Task:

1. Check Option for Deletion: The task checks if the DELETE_TEMPORARY_OBJECTS option is enabled in the Knowledge Module.
• If yes, the table will be dropped.
• If no, the table is preserved for debugging purposes.
2. Drop the Loading Table:
• The drop table command is executed to remove the loading table from the target (staging area).
3. Ignore Errors:
• The task will ignore any errors related to the non-existence of the table (if the table doesn't exist), ensuring that the task doesn't stop the mapping process.