关于SELECT 逻辑的执行顺序问题
不会有大多数人都和我一样的认为，是先进行的Where 剔除结果集，再进行Join的吧
SQL server 2014 逻辑执行标准：
https://msdn.microsoft.com/en-us/library/ms189499(v=sql.120).aspx
FROM
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FROM
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ON
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JOIN
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WHERE
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GROUP BY
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WITH CUBE or WITH ROLLUP
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HAVING
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SELECT
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DISTINCT
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ORDER BY
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TOP
Oracle 12c 逻辑执行标准
http://docs.oracle.com/cd/B19306_01/server.102/b14200/statements_10002.htm