零件关系P（零件名，条形码，供应商，产地，价格）中的（ ）属性可以作为该关系的主键。查询产于西安且名称为“P2”的零件，结果以零件名、供应商及零件价格分列表示，对应的SQL语句为：
SELECT零件名，供应商，价格
FROM P
WHERE零件名=’P2’ AND（ ））;
问题1选项
A.零件名
B.条形码
C.产地
D.供应商
问题2选项
A.条形码=西安
B.条形码=’西安’
C.产地=西安
D.产地=’西安’
正确答案及解析
正确答案
解析
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