NOPI tables can be skewed in specific cases. If a small table is loaded with a fast load, skew inevitably occurs because the data is not sent to the AMPs row by row but in 64KB or more giant blocks. Teradata may send all rows to the same AMP and one data block. AMP-local copying of the rows will be applied when executing an "INSERT...SELECT" statement from a primary index table into a NOPI table. All rows stay on their current AMP, and if the primary index table is skewed, the NOPI table will be skewed. Skew can be avoided using the HASH BY RANDOM option; data blocks are distributed randomly, resulting in an even distribution. INSERT INTO Customer SELECT * FROM Customer_2020 HASH BY RANDOM; If you want to distribute on row level to achieve even better randomness, you can use this statement: INSERT INTO Customer SELECT * FROM Customer_2020 HASH BY RANDOM (1,100000000); Furthermore, skewing of a NOPI table can happen by executing an archive job on one system and restoring the backup on a different system.