In general, a nested loop join with sort composite is favored by the optimizer if the inner index is well-clustered and the inner table is expected to be probed many times.

一般来说，如果内部索引是良好的集群且预测内部表被多次探测，则使用复合排序的嵌套循环联将受到优化器的青睐。

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Then for each row from the fact table scan, the foreign key is also hashed and probed into the bit vector to determine whether the current fact table row is filtered out.

然后针对事实表扫描的每一行，外键也被散列并探测到位向量中，从而判断当前的事实表行是否被过滤掉了。

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