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Explanation:

The ALTER TABLE ... RENAME TO command is a metadata-only operation.

Metastore Update: It simply changes the entry in the Hive Metastore or Unity Catalog to map the new table name to the existing storage location.
No Data Movement: The underlying Delta format data directory, its transaction log (_delta_log), and all Parquet data files remain in their original location (/mnt/production/saledata_by_store) and are completely untouched.
No Transaction Log Entry: Because the Delta transaction log tracks changes to the data and schema inside the directory, a metadata rename in the catalog does not trigger a new commit in the Delta log itself.
Efficiency: This is a nearly instantaneous operation because it does not involve costly I/O or file relocation.

Explanation:

The ALTER TABLE ... RENAME TO command is a metadata-only operation.

Metastore Update: It simply changes the entry in the Hive Metastore or Unity Catalog to map the new table name to the existing storage location.
No Data Movement: The underlying Delta format data directory, its transaction log (_delta_log), and all Parquet data files remain in their original location (/mnt/production/saledata_by_store) and are completely untouched.
No Transaction Log Entry: Because the Delta transaction log tracks changes to the data and schema inside the directory, a metadata rename in the catalog does not trigger a new commit in the Delta log itself.
Efficiency: This is a nearly instantaneous operation because it does not involve costly I/O or file relocation.

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A Delta Lake table named production.saledata_by_user was initially created with the following query:

CREATE TABLE production.saledata_by_user 
USING DELTA 
LOCATION "/mnt/production/saledata_by_store"

CREATE TABLE production.saledata_by_user 
USING DELTA 
LOCATION "/mnt/production/saledata_by_store"

Recognizing a typographical error in the table name, the developer executed the following command:

ALTER TABLE production.saledata_by_user RENAME TO production.saledata_by_store

ALTER TABLE production.saledata_by_user RENAME TO production.saledata_by_store

What is the outcome of running this second command?

Real Exam

Last updated: January 6, 2026 at 15:42

The table reference in the metastore is updated, and all underlying data files are relocated to a new path matching the table name.

13.0%

The table reference in the metastore is updated, but no data movement or changes to the underlying files occur.

69.6%

The rename operation is recorded as a new version in the Delta transaction log.

8.7%

A new Delta transaction log is initiated in the storage path for the renamed table.

8.7%