MERGE JOIN CARTESIAN 联结 ; 笛卡尔积 ; 笛卡儿联结
The Cartesian join is reduced by the filters found in the join expressions from each dimension to the fake fact.
由于伪事实的每个维度中的连接表达式的过滤,笛卡尔连接结果缩小了。
For example 10,000 rows in one dimension multiplied by 10,000 rows in another would produce a Cartesian join of 100,000,000 rows.
例如,一个维度中10,000行乘以另一个维度的10,000行会产生100,000,000行的Cartesian连接。
For example, write indexable or stage 1 predicates and avoid writing queries without join predicates (also known as Cartesian join).
例如,编写可索引或一阶谓词,尽量不要编写没有连接谓词(也称为 Cartesian 连接)的查询。
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