1、USE pubs

SELECT au_lname, state
FROM authors
WHERE state = 'CA' OR state = 'IN' OR state = 'MD'
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2、USE pubs

SELECT au_lname, state
FROM authors
WHERE state IN ('CA', 'IN', 'MD')
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上面两条查询语句，同时查询一个有5万条数据的数据库，哪一个的查询速度快？？？？？？？？？？
为什么？？？？？？？why???why????why????

急待解答!!!!!!!!!!