单选题Which statement describes the effect on an index, when the indexed column for the rows is updatedin the base table()AAn update in a leaf row takes place.BThe index becomes invalid after the update.CThe leaf block containing the row to be updated is marked as invalid.DA row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted
单选题
Which statement describes the effect on an index, when the indexed column for the rows is updatedin the base table()
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 logically deleted and a new leaf row is inserted
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