- A.P1（零件号，零件名称，单价）、P2（供应商，供应商所在地，库存量）
- B.P1（零件号，零件名称）、P2（供应商，供应商所在地，单价，库存量）
- C.P1（零件号，零件名称）、P2（零件号，供应商，单价，库存量）、P3（供应商，供应商所在地）
- D.P1（零件号，零件名称）、P2（零件号，单价，库存量）、P3（供应商，供应商所在地）、P4（供应商所在地，库存量）
正确答案及解析
正确答案
解析
为了解决关系P存在冗余以及插入异常和删除异常等问题，需要将零件关系P分解。选项A、选项B和选项D是有损连接的，且不保持函数依赖故分解是错误的，例如，分解为选项A、选项B和选项D后，用户无法查询某零件由哪些供应商供应，原因是分解足有损连接的，且不保持函数依赖。
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