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“雇员”表在LAST_NAME列上有一个名为LN_IDX的索引。您要将此索引更改为FIRST_NAME列的索引。以下哪条SQL语句将实现此操作()

  • A、ALTER INDEX ln_idx ON employees(first_name)
  • B、ALTER INDEX ln_idx TO employees(first_name)
  • C、ALTER INDEX ln_idx TO fn_idx ON employees(first_name)
  • D、以上都不能;您无法变更索引

参考答案

更多 ““雇员”表在LAST_NAME列上有一个名为LN_IDX的索引。您要将此索引更改为FIRST_NAME列的索引。以下哪条SQL语句将实现此操作()A、ALTER INDEX ln_idx ON employees(first_name)B、ALTER INDEX ln_idx TO employees(first_name)C、ALTER INDEX ln_idx TO fn_idx ON employees(first_name)D、以上都不能;您无法变更索引” 相关考题
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