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[问答题] 摩擦学新材料研究

Examine the structure of the EMPLOYEES table: Column name Data type Remarks EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2(30) JOB_ID VARCHAR2(20) NOT NULL SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You need to create a view called EMP_VU that allows the users to insert rows through the view. Which SQL statement, when used to create the EMP_VU view, allows the users to insert rows?() ["CREATE VIEW emp_vu AS SELECT employee_id, emp_name, department_id FROM employees WHERE mgr_id IN (102, 120);","CREATE VIEW emp_vu AS SELECT employee_id, emp_name, job_id, department_id FROM employees WHERE mgr_id IN (102, 120);","CREATE VIEW emp_vu AS SELECT department_id, SUM(sal) TOTALSAL FROM employees WHERE mgr_id IN (102, 120) GROUP BY department_id;","CREATE VIEW emp_vu AS SELECT employee_id, emp_name, job_id, DISTINCT department_id FROM employee"] 李先生,腹部被车撞伤5h,腹痛明显,伴面色苍白,四肢厥冷,体检:血压75/55mmHg,脉率140/min,全腹轻度压痛、反跳痛、肌紧张,腹部透视无异常发现。腹腔穿刺抽出不凝血液。 该患者腹腔穿刺液中血液不凝固的原因是()   ["凝血因子消耗","出血量过大","凝血功能障碍","腹膜有脱纤维作用","误穿人血管"] 《说文解字》的作者是东汉时的班固。 主要依靠人来完成服务过程的服务,如美容、教学等被称为() ["高接触性服务","高技术性服务","连续性服务","间断性服务"] 隧道完成后的净总宽应为(),否则将被扣分。 ["设计值±10mm","设计值±15mm","设计值±20mm","不小于设计值"] 摩擦学新材料研究
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