單項(xiàng)選擇題
查看以下語(yǔ)句:CRATETABLEorders(serial__noNUMBERUNIQUE,order__idNUMBERPRIMARYKEY,order__dateDATENOTNULL,statusVARCHAR2CHECK(statusIN("CREDIT","CASH")),product__idNUMBERREFERENCESproducts(product__id),order__totalNUMBER);將自動(dòng)針對(duì)表中的哪兩列創(chuàng)建索引()
A.ORDER_ID
B.SERIAL_NO
C.ORDER_TOTAL
D.STATUS
E.ORDER_DATE
F.PRODUCT_ID
A.ORDER_ID
B.SERIAL_NO
C.ORDER_TOTAL
D.STATUS
E.ORDER_DATE
F.PRODUCT_ID