Typically, the optimizer chooses merge scan join when the cardinality of the outer input is not obviously small and there is no efficient access method for the inner table.
通常情况下，在外部输入的基数显然不小且对于内部表没有一种有效的访问方法时，优化器会选择合并扫描联接。
Now that's obviously small, but it is growing.
目前看来它显然只占很小的份额，但是却在增长中。
Obviously, small miscellaneous grain has comprehensive benefit and power of competition in agricultural production.
可见，小杂粮在农业生产中具有显著的综合效益和产业竞争力。
Obviously, small miscellaneous grain has comprehensive benefit and power of competition in agricultural production.
可见，小杂粮在农业生产中具有显著的综合效益和产业竞争力。
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