DATABRICKS-DEP Question 67

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• Chose A0

  - Correct answer : A — The 40 MB write likely falls below the size threshold for clustering-on-write with two clustering columns on a Unity Catalog managed table, so the new files may not be clustered until a subsequent `OPTIMIZE` runs. A . Clustering-on-write only engages once accumulated new data crosses a size threshold that scales with the number of clustering columns; for two clustering columns on a Unity Catalog managed table that threshold is 256 MB, so a 40 MB transaction is likely to land unclustered until a later `OPTIMIZE` incrementally reorganizes it. B . Clustering on write is threshold-based rather than unconditional, so small writes below the applicable size threshold are not guaranteed to be clustered immediately; only writes at or above the threshold trigger clustering at write time. C . `OPTIMIZE FULL` is used to recluster all existing data the first time clustering keys are set or changed, but liquid clustering itself, including clustering-on-write behavior for sufficiently large transactions, is active from table creation and does not wait for a manual full optimize. D . Incremental clustering only rewrites the files necessary to accommodate new data relative to the current clustering keys; it does not force a rewrite of the entire historical table on every write, which is precisely what makes liquid clustering more efficient than repartitioning.