下列哪种关系运算不要求:“R和S具有相同的属性个数,并且每对相对应的属性都具有相同的域”?
D
暂无解析
Whatisnotthemeetinglayout?
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CignaInsuranceCompanyoffersemployeestheoptionofplacingtake-outmealorderswiththecompanychef.
Exercisephysiologist