A.SELECT*FROM訂單WHERE SUBSTR(訂購(gòu)單號(hào),4)=,,1” B.SELECT*FROM訂單WHERE SUBSTR(訂購(gòu)單號(hào),4,1卜,,1” C.SELECT*FROM訂單WHERE”1”$訂購(gòu)單號(hào) D.SELECT*FROM訂單WHERE RIGHT(訂購(gòu)單號(hào),1)="1”
A.ALTER TABLE stock股票名稱WITH c(10) B.ALTER TABLE stock股票名稱c(10) C.ALTER TABLE stock ALTER股票名稱c(10) D.ALTER stock ALTER股票名稱c(10)
A.數(shù)值型 B.字符型 C.時(shí)間日期型 D.時(shí)間型