若S中有30行记录，执行以下SQL语句SELECT * FROM S A, S BWHERE A.CITY =B.CITY则运行结果的最大可能记录数maxNum和最小可能记录数minNum分别是—— A: maxNum=30, minNum=0 B: maxNum=60, minNum=30 C: maxNum=900, minNum=30 D: maxNum=900, minNum=60

假设有模板定义如下： A: templatefloatMin(Tm1,Tm2){return(m1} B: templateT1Min(T1m1,T2m2){return(m1} C: templateT1Min(T1a[],T2n){T1minnum=a[0];for(inti=0;iif(minnum>a[i])minnum=a[i];returnminnum;} D: templateTMin(Tm1,Tm2,Tm3){Ttemp=Min(m1,m2);returnMin(temp,m3);}

假设有模板定义如下：template T Min(T m1, T m2 ){return (m1 A: template float Min(T m1, T m2 ){return (m1 B: template T1 Min(T1 a[ ], T2 n ){T1 minnum=a[0] ;for (int i=0 ;ia[i]) minnum=a[i];return minnum;} C: template T1 Min(T1 m1, T2 m2 ){return (m1 D: template T Min(T m1, T m2, T m3 ){T temp=Min(m1,m2) ;return Min(temp , m3) ;}