Joining NoPI table and Target table with PI

Database
KVB
Enthusiast

Joining NoPI table and Target table with PI

Hi

I load my stage table with NoPI for faster loading.Later i am joining the stage with the target on some columns.How does it affect as I am joining NoPI table with PI table?

1 REPLY
Teradata Employee

Re: Joining NoPI table and Target table with PI

In case of tables with PIs the rows are distributed among the AMPs based on the hash values of the PI, in the case of a NOPI table the rows are randomly distributed among the AMPs. Which means that in the case of a NOPI join we will always have to do a full table scan of the table, which will be significantly slower than a PI on PI join.

Hope this helps.

Farhan