count与count(*)的区别是()。A、无区别B、count是聚合函数,count(*)不是聚合函数C、count统计空格而COUNT(×)不统计D、count(*)统计NULL值,而COUNT不统计
count与count(*)的区别是()。
- A、无区别
- B、count是聚合函数,count(*)不是聚合函数
- C、count统计空格而COUNT(×)不统计
- D、count(*)统计NULL值,而COUNT不统计
相关考题:
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