单项选择题
A.REPORT FROM PP1 PREVIEW B.DO FROM PP1 PREVIEW C.REPORT FORM PP1 PREVIEW D.DO FORM PP1 PREVIEW
A.SELECT 平均工资 FROM 职工 B.SELECT AVG(工资) FROM 职工 C.SELECT SUM(工资) FROM 职工 D.SELECT COUNT(工资) FROM 职工
A.30 B.10 C.0 D.-2