I'm running a insert query which inserts data in 30 iterations. After 16 iterations the record count in the target table is 3 billion. The 17th iteration is taking alomst 7 hours to load the data. Is there any way to speed-up the process time (load time).
If you don't have a unique index, try to create the table as a Multiset table. Then Teradata does not need to check for row dupilicates at every insert.
Adding partitioning might help.
Can you show the table DDL plus the Insert/Selects?
Why do you need to run so many iterations?