问题详情

建立一个视图salary,该视图包括了系号和(该系的)平钧工资两个字段,正确的是SQL语句是A）CREATE VIEW salaryAS系号，AVG（工资）AS平均工资FROM教师；GROUP BY系号B) CREATE VIEW salary AS SELECT系号，AVG(工资)AS平均工资FROM教师；GROUP BY系名C) CREATE VIEW salary SELECT系号，AVG(工资）AS平均工资FROM教师；GROUP BY系号D）CREATE VIEW salary AS SELECT系号，AVG（工资）As平均工资FROM教师；GROUP BY系号