17. The SCOTT user has an index on the ITEM_DESC column of the ITEM table. As part of the year-ending task, SCOTT updates the ITEM_DESC column for most of the rows in the ITEM table. How does this change to the table affect the index?
A. An update in a leaf row takes place.
B. The index becomes invalid after the update.
C. The leaf block containing the row to be updated is marked as invalid.
D. A row in the leaf block of the index for the key value is deleted and inserted.
答案：D
每年用户一个表上的一个列，那么在这个列上的索引，行数据在索引leaf block的值会删除再被插入(估计是便于维护), 索引叶子节点包括rowid(需实验)
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/11312660/viewspace-718497/ ，如需转载，请注明出处，否则将追究法律责任。
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