問題文
A very large table has a column that the application no longer reads. The team wants to stop the column from appearing at once, and wants to release the space it uses in a later maintenance window. What do the two steps look like?
選択肢
- Mark the column unused now, which hides it right away and releases its space, and set it used again later if the application needs the values.
- Mark the column unused now, which hides it right away without touching the stored rows, and drop the unused columns later to release the space.
- Drop the column now, which hides it right away without touching the stored rows, and mark the dropped columns unused later to release the space.
- Rename the column now, which hides it right away without touching the stored rows, and drop the renamed column later to release the space.