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SQL-UsingCrossJoins
2015-11-21 02:04:08 来源: 作者: 【 】 浏览:0
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A cross join that does not have a WHERE clause produces the Cartesian product of the tables involved in the join. The size of a Cartesian product result set is the number of rows in the first table multiplied by the number of rows in the second table.

However, if a WHERE clause is added, the cross join behaves as an inner join.

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