聽說這裏有很多sql高手，有個簡單問題請教

最近公司緊縮開支，把另外一個職位的sql工作也交給我幹。可是，我以前很少做這方麵的工作，不太熟悉，有問題請教。謝謝！

Q: 有個table名叫person, has 4 fields, ID, Sales, Date, Rank
For example:
ID Sales Date Rank
10 10000 1/1 0
10 20182 1/2 1
20 10000 1/1 0
20 29765 1/2 1
20 23456 1/3 1

Now, for each unique ID, I want to select the highest rank, if there are two rows with equally highest rank, randomly select one.

The result table looks like
ID Sales Date Rank
10 20182 1/2 1
20 29765 1/2 1

OR
ID Sales Date Rank
10 20182 1/2 1
20 23456 1/3 1

叩謝！