A.alter table emp delete column addcolumn; B.alter table emp modify column addcolumn char(10); C.alter table emp change addcolumn addcolumn int; D.alter table emp add column addcolumn int;
A.DROP USER B.DROP TABLE USER C.DELETE USER D.DELETE FROM USER
若用如下的SQL語句創(chuàng)建了一個表SC:() CREATE TABLE SC(S# CHAR(6) NOT NULL,C# CHAR(3) NOT NULL,SCORE INTEGER, NOTE CHAR(20));向SC表插入如下行時,()行可以被插入。
A.(NULL,’103’,80,’選修’) B.(’200823’,’101’,NULL,NULL) C.(’201132’,NULL,86,’’) D.(’201009’,’111’,60,必修)