For example, this might happen when two ore more of the tables in the MQT have a referential integrity relationship defined and the join predicate is on their primary key - foreign key columns.

例如，当MQT中的两个或多个表定义了引用完整性关系并且联结谓词在它们自己的主键-外键列上时，就会出现这种情况。

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Rising domestic iron ore production and slowing steel demand have hit some foreign miners.

国内铁矿产量的增加和对钢材需求的放缓需求”对外国供应商造成冲击。

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Research on continuous ore drawing and haulage equipment for underground metal mines has widely been done in main foreign countries with mining industry.

国外主要矿业国家对地下金属矿山连续出矿运矿设备进行了深入的研究。

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China is the lead consumer of Brazilian soybeans and iron ore, not to mention a new foreign direct investor in Brazilian natural resources and infrastructure.

FORBES: Brazil VP Tells China Delegation: Country Getting China Wary

Tata, which mines all the iron ore and coal it needs, now aims to carry out primary steel production close to its iron-ore deposits, and then ship semi-finished steel for finishing close to foreign consumer markets.

ECONOMIST: Why the Tata-Corus deal makes sense for both parties