DeltaTable gives Python code a table-oriented interface for updates and merges. Read the change batch as a DataFrame, assign source and target aliases, and define the key comparison. The chained methods describe matched and unmatched actions; execute commits the merge. Building the chain without execute does not write rows.
Aster Supply's change batch updates existing orders and introduces a new identifier. A matched update and an unmatched insert solve different parts of that feed. A not-matched-by-source delete has a stronger meaning: it assumes that the source covers the complete population you want to retain. Applying it to a partial change batch can erase unrelated orders. The final task makes that full-snapshot assumption explicit. Every exercise starts from the same saved target and checks its rows after the write, including on a second dataset. You may also express an equivalent change with SQL.