单选题Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2 (25) LAST_NAME VARCHAR2 (25) HIRE_DATE DATE Which UPDATE statement is valid? （）A UPDATE employees SET first_name = 'John' SET last_name = 'Smith' WHERE emp

第1题：

Which three statements inserts a row into the table?（）

• A、INSERT INTO employees   VALUES ( NULL, ‘John’,‘Smith’);
• B、INSERT INTO employees( first_name, last_name)   VALUES(‘John’,‘Smith’);
• C、INSERT INTO employees   VALUES (‘1000’,‘John’,NULL);
• D、INSERT INTO employees(first_name,last_name, employee_id)   VALUES ( 1000, ‘John’,‘Smith’);
• E、INSERT INTO employees (employee_id)   VALUES (1000);
• F、INSERT INTO employees (employee_id, first_name, last_name)   VALUES ( 1000, ‘John’,‘’);

第2题：

Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE You issue these statements: CREATE table new_emp ( employee_id NUMBER, name VARCHAR2(30)); INSERT INTO new_emp SELECT employee_id , last_name from employees; Savepoint s1; UPDATE new_emp set name = UPPER(name); Savepoint s2; Delete from new_emp; Rollback to s2; Delete from new_emp where employee_id =180; UPDATE new_emp set name = 'James'; Rollback to s2; UPDATE new_emp set name = 'James' WHERE employee_id =180; Rollback; At the end of this transaction, what is true?（）

• A、You have no rows in the table.
• B、You have an employee with the name of James.
• C、You cannot roll back to the same savepoint more than once.
• D、Your last update fails to update any rows because employee ID 180 was already deleted.

第3题：

Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) Which three statements insert a row into the table? （）

• A、INSERT INTO employees VALUES (NULL, 'John', 'smith');
• B、INSERT INTO employees (first_name, last_name) VALUES ('John', 'smith');
• C、INSERT INTO employees VALUES ('1000, 'John', 'smith');
• D、INSERT INTO employees (first_name, last_name, employee_id) VALUES (1000, 'John', 'smith');
• E、INSERT INTO employees (employee_id) VALUES (1000);
• F、INSERT INTO employees ( employee_id, first_name, last_name, ) VALUES (1000, 'John','');

第4题：

Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2 (25) LAST_NAME VARCHAR2 (25) HIRE_DATE DATE Which UPDATE statement is valid? （）

• A、UPDATE employees SET first_name = 'John' SET last_name = 'Smith' WHERE employee_id = 180;
• B、UPDATE employees SET first_name = 'John', SET last_name = 'Smoth' WHERE employee_id = 180;
• C、UPDATE employee SET first_name = 'John' AND last_name = 'Smith' WHERE employee_id = 180;
• D、UPDATE employee SET first_name = 'John', last_name = 'Smith' WHERE employee_id = 180;

第5题：

Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE You issue these statements: CREATE table new_emp ( employe_id NUMBER, name VARCGAR2(30)); INSERT INTO new_emp SELECT employee_id, last_name from employees; Savepoint s1; UPDATE new_emp set name = UPPER(name); Savepoint s2; Delete from new_emp; Rollback to s2; Delete from new_emp where employee_id=180; UPDATE new_emp set name = 'James'; Rollback to s2; UPDATE new_emp sey name = 'James' Where employee_id=180; Rollback; At the end of this transaction, what is true?（）

• A、You have no rows in the table.
• B、You have an employee with the name of James.
• C、You cannot roll back to the same savepoint more than once.
• D、Your last update fails to update any rows because employee ID 180 was already deleted.

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第13题：

Examine the description of the EMPLOYEES table: EMP_ID NUMBER(4) NOT NULL LAST_NAME VARCHAR2(30) NOT NULL FIRST_NAME VARCHAR2(30) DEPT_ID NUMBER(2) Which statement produces the number of different departments that have employees with last name Smith?（）

• A、SELECT COUNT(*) FROM employees WHERE last_name='Smith';
• B、SELECT COUNT(dept_id) FROM employees WHERE last_name='Smith';
• C、SELECT DISTINCT(COUNT(dept_id)) FROM employees WHERE last_name='Smith';
• D、SELECT COUNT(DISTINCT dept_id) FROM employees WHERE last_name='Smith';
• E、SELECT UNIQUE(dept_id) FROM employees WHERE last_name='Smith';

第14题：

Examine the structure of the EMPLOYEES and NEW_EMPLOYEES tables: EMPLOYEES EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE NEW_EMPLOYEES EMPLOYEE_ID NUMBER Primary Key NAME VARCHAR2 (60) Which DELETE statement is valid?（）

• A、DELETE FROM employees WHERE employee_id = (SELECT employee_id FROM employees);
• B、DELETE * FROM employees WHERE employee_id = (SELECT employee_id FROM new_ employees);
• C、DELETE FROM employees WHERE employee_id IN (SELECT employee_id FROM new_employees WHERE name = 'carrey');
• D、DELETE * FROM employees WHERE employee_id IN (SELECT employee_id FROM new_employees WHERE name = 'carrey');

第15题：

Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE Which UPDATE statement is valid?（）

• A、UPDATE employees SET first_name = 'John' SET last_name ='Smith' WHERE employee_id = 180;
• B、UPDATE employees SET first_name = 'John', SET last_name ='Smith' WHERE employee_id = 180;
• C、UPDATE employees SET first_name = 'John' AND last_name ='Smith' WHERE employee_id = 180;
• D、UPDATE employees SET first_name = 'John', last_name ='Smith' WHERE employee_id = 180;

第16题：

Examine the structure of the EMPLOYEES and NEW_EMPLOYEES tables: EMPLOYEES EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE NEW_EMPLOYEES EMPLOYEE_ID NUMBER Primary Key NAME VARCHAR2(60) Which UPDATE statement is valid?（）

• A、UPDATEnew_employeesSETname=（SELECTlast_nameFirst_nameFROMemployeesWHEREemployee_id=180）WHEREemployee_id=180；
• B、UPDATEnew_employeesSETname=（SELECTlast_nameFirst_nameFROMemployees）WHEREemployee_id=180；
• C、UPDATEnew_employeesSETname=（SELECTlast_nameFirst_nameFROMemployeesWHEREemployee_id=180）   WHEREemployee_id=（SELECTemployee_idFROMnew_employees）；
• D、UPDATEnew_employeesSETname=（SELECTlast_nameFirst_nameFROMemployeesWHEREemployee_id=（SELECTemployee_idFROMnew_employees）   WHEREemployee_id=180；

第17题：

Examine the structure of the EMPLOYEES and NEW_EMPLOYEES tables: EMPLOYEES EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE NEW_EMPLOYEES EMPLOYEE_ID NUMBER Primary Key NAME VARCHAR2(60) Which DELETE statement is valid?（）

• A、DELETE FROM employees WHERE employee_id = (SELECT employee_id FROM employees);
• B、DELETE * FROM employees WHERE employee_id = (SELECT employee_id FROM new_employees);
• C、DELETE FROM employees WHERE employee_id IN (SELECT employee_id FROM new_employees WHERE name ='Carrey');
• D、DELETE * FROM employees WHERE employee_id IN (SELECT employee_id FROM new_employees WHERE last_name ='Carrey');

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