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设有表M,将其中的Type列的数据类型改为NCHAR(4)。下列能实现该功能的语句是()。

  • A、ALTER  TABLE  M  ADD  COLUMN  Type  NCHAR(4)
  • B、ALTER  TABLE  M  ALTER  COLUMN  Type  NCHAR(4)
  • C、ALTER  TABLE  M  DROP  COLUMN  Type  NCHAR(4)
  • D、ALTER  TABLE  M  ALTER  Type  NCHAR(4)

参考答案

更多 “设有表M,将其中的Type列的数据类型改为NCHAR(4)。下列能实现该功能的语句是()。A、ALTER  TABLE  M  ADD  COLUMN  Type  NCHAR(4)B、ALTER  TABLE  M  ALTER  COLUMN  Type  NCHAR(4)C、ALTER  TABLE  M  DROP  COLUMN  Type  NCHAR(4)D、ALTER  TABLE  M  ALTER  Type  NCHAR(4)” 相关考题
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