[ibarrac]

Teradata is meant for data warehousing and analysis with lots of reads and few writes, not for OLTP that has a lot of writes.

Any DML that modifies a row in Teradata either locks the whole table if it doesn't know immediately where the row is, or locks the row hash if it does (if you give it the primary index value). Locking the whole table involves sending a command to all of the nodes and waiting for a response. That's why most writes are typically done as large batch loads at infrequent times.