The EMPLOYEE tables has these columns: LAST_NAME VARCHAR2(35) SALARY NUMBER(8,2) COMMISSION_PCT NUMBER(5,2) You want to display the name and annual salary multiplied by the commission_pct for all employees. For records that have a NULL commission_pct, a zero must be displayed against the calculated column. Which SQL statement displays the desired results? ()
A. SELECT last_name, (salary * 12) * commission_pct FROM EMPLOYEES;
B. SELECT last_name, (salary * 12) * IFNULL(commission_pct, 0) FROM EMPLOYEES;
C. SELECT last_name, (salary * 12) * NVL2(commission_pct, 0) FROM EMPLOYEES;
D. SELECT last_name, (salary * 12) * NVL(commission_pct, 0) FROM EMPLOYEES
查看答案
调车作业遇有特殊情况,可由有任免权限的单位鉴定、考试合格的()担任指挥工作。
A. 连结员
B. 货运员
C. 客运员
D. 制动员
带电更换220kV绝缘子或在绝缘子串上作业,应保证作业中良好绝缘子片数不得少于7片。
A. 正确
B. 错误
眼观病变颜面和身体天然孔周围的皮下组织充血、水肿,呈特征性狮子头症状的是()
A. 兔病毒性出血病
B. 兔黏液瘤病
C. 水貂阿留申病
D. 水貂病毒性肠炎
E. 白僵病
当提高稳定塔塔顶压力时,会影响()。
A. 塔底液位
B. 稳定塔进料量
C. 产品蒸汽压
D. 产品出装置量