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原创 SQL ZOO 难题整理

SQL ZOO难题整理SELECT worldSELECT nobel SELECT world EOR Exclusive OR (XOR). Show the countries that are big by area (more than 3 million) or big by population (more than 250 million) but not both. Show name, population and area. 要么1，要么2，不能都占 SELECT name, po