A SELECT statement can be used to perform these three functions: 1. Choose rows from a table. 2. Choose columns from a table 3. Bring together data that is stored in different tables by creating a link between them. Which set of keywords describes these capabilities?()
- A、difference, projection, join
- B、selection, projection, join
- C、selection, intersection, join
- D、intersection, projection, join
- E、difference, projection, product
正确答案:B
答案解析:有

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