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SQL,sql教程

SQL,sql教程


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.

www.htsjk.Com true http://www.htsjk.com/shujukunews/7113.html NewsArticle SQL,sql教程 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 o...
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