Dear DWHPro reader,

UPDATE looks identical in SQL — but in Teradata and Snowflake, it works in completely different ways.

Teradata updates data blocks in place with journals and WAL.

Snowflake rewrites partitions and commits through metadata.

The impact? Different performance, rollback behavior, and tuning strategies.

👉 Read the full article: Read now...

Best,

Roland Wenzlofsky

Author of “Teradata Query Performance Tuning”