i prefer to use aliases for my updates, because the format for SQL makes it easy to include a SELECT statement very easily, which lets me do a quick Sanity Check by running the SELECT portion with the identical criteria.
how does this work for you?
SET MyTarget.EstimatedDeletedDate = 1
--highlight and execute starting at the SELECT
FROM VehicleWorld MyTarget
WHERE NOT EXISTS
(SELECT 1 FROM VCFS_Production..CORE_VehicleAdSearch ads
WHERE MyTarget.Vehicle_ID = ads.Vehicle_ID)
AND MyTarget.EstimatedDeletedDate <> 1
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