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如何使用表中不同数量的列设计数据库

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Let us say that you are creating a system to store characteristics of different countries. There will be same basic columns like name, population, capital city etc. But let us say in addition to it you want to store some country specific information like highest mountain, nearest ocean, most famous food etc. These columns will be different for each country. Let us say that you are creating a system to st




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