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您要对EMPLOYEES表的FIRST_NAME和LAST_NAME列创建一个组合索引。以下哪条语句将完成此任务（）
- A、CREATE INDEXfl_idx ON employees（first_name last_name）
- B、CREATE INDEXfl_idx ON employees（first_name），employees（last_name）
- C、CREATE INDEXfl_idx ON employees（first_name，last_name）
- D、CREATE INDEXfl_idx ON employees（first_name）；CREATE INDEXfl_idx ON employees（last_name）
参考答案
更多 “您要对EMPLOYEES表的FIRST_NAME和LAST_NAME列创建一个组合索引。以下哪条语句将完成此任务（）A、CREATE INDEXfl_idx ON employees（first_name last_name）B、CREATE INDEXfl_idx ON employees（first_name），employees（last_name）C、CREATE INDEXfl_idx ON employees（first_name，last_name）D、CREATE INDEXfl_idx ON employees（first_name）；CREATE INDEXfl_idx ON employees（last_name）” 相关考题
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您在“雇员”表的一个子集上创建了名为EMPLOYEES_VIEW的视图。用户AUDREY需要使用此视图创建报表。只有您和Audrey具有此视图的访问权限。应执行下列哪项操作（）A、不执行任何操作。Audrey做为数据库用户，他的用户帐户已自动被授予对所有数据库对象的SELECT权限B、GRANT SELECT ON employees_viewTO publicC、GRANT SELECT ON employees_viewTO audreyD、GRANT SELECT ON employees AND employees_view TO audrey
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单选题您在公司的数据库中成功创建了名为SALARY的表。您现在要通过向引用EMPLOYEES表的匹配列的SALARY表添加FOREIGNKEY约束条件来建立EMPLOYEES表与SALARY表之间的父/子关系。尚未向SALARY表添加任何数据。应执行以下哪条语句（）A
ALTER TABLE salary ADD CONSTRAINT fk_employee_id_01 FOREIGN KEY（employee_id）REFERENCES employees（employee_id）B
ALTER TABLE salary ADD CONSTRAINT fk_employee_id_ FOREIGN KEY BETWEEN salary（employee_id）AND employees（employee_id）C
ALTER TABLE salary FOREIGN KEY CONSTRAINT fk_employee_id_REFERENCES employees（employee_id）D
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考题
多选题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? （）AINSERT INTO employees VALUES (NULL, 'John', 'smith');BINSERT INTO employees (first_name, last_name) VALUES ('John', 'smith');CINSERT INTO employees VALUES ('1000, 'John', 'smith');DINSERT INTO employees (first_name, last_name, employee_id) VALUES (1000, 'John', 'smith');EINSERT INTO employees (employee_id) VALUES (1000);FINSERT INTO employees ( employee_id, first_name, last_name, ) VALUES (1000, 'John','');
考题
多选题Which three statements inserts a row into the table?（）AINSERT INTO employees VALUES ( NULL, ‘John’,‘Smith’);BINSERT INTO employees( first_name, last_name) VALUES(‘John’,‘Smith’);CINSERT INTO employees VALUES (‘1000’,‘John’,NULL);DINSERT INTO employees(first_name,last_name, employee_id) VALUES ( 1000, ‘John’,‘Smith’);EINSERT INTO employees (employee_id) VALUES (1000);FINSERT INTO employees (employee_id, first_name, last_name) VALUES ( 1000, ‘John’,‘’);
考题
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 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;
考题
单选题You own a table called EMPLOYEES with this table structure: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE What happens when you execute this DELETE statement? DELETE employees; （）A
You get an error because of a primary key violation.B
The data and structure of the EMPLOYEES table are deleted.C
The data in the EMPLOYEES table is deleted but not the structure.D
You get an error because the statement is not syntactically correct.
考题
单选题如果希望更新表authors中的first_name列为非空，那么可以使用哪个语句？（）A
alter table authors add first_name not nullB
alter table authors modify first_name not nullC
alter table authors alter first_name not nullD
alter table authors drop first_name not null
考题
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 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;
考题
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 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;
考题
多选题Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) Which three statements inserts a row into the table? （）AINSERT INTO employees VALUES (NULL, 'JOHN','Smith');BINSERT INTO employees( first_name, last_name) VALUES ('JOHN','Smith');CINSERT INTO employees VALUES ('1000','JOHN','NULL');DINSERT INTO employees(first_name,last_name, employee_id) VALUES ('1000, 'john','Smith');EINSERT INTO employees (employee_id) VALUES (1000);FINSERT INTO employees (employee_id, first_name, last_name) VALUES ( 1000, 'john',);
考题
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 INSERT statement is valid? （）A
INSERT INTO employees (employee_id, first_name, last_name, hire_date) VALUES (1000, 'John', 'smith','01/01/01);B
INSERT INTO employees(employee_id, first_name, last_name, hire_date) VALUES (1000, 'John', 'smith','01 january 01');C
INSERT INTO employees(employee_id, first_name, last_name, Hire_date) VALUES (1000, 'John', 'smith', To_ date ('01/01/01));D
INSERT INTO employees(employee_id, first_name, last_name, hire_date) VALUES (1000, 'John', 'smith','01-Jan-01');
考题
单选题“雇员”表包含以下列： EMPLOYEE_ID NOT NULL, Primary Key SSNUM NOT NULL, Unique LAST_NAME VARCHAR2(25) FIRST_NAME VARCHAR2(25) DEPARTMENT_ID NUMBER 部门表中 DEPARTMENT_ID 列的外键 SALARY NUMBER(8,2) 如果执行以下语句： CREATE INDEX emp_name_idx ON employees(last_name, first_name); 以下哪个说法是的（）A
此语句会创建一个基于函数的索引B
因为语法错误，此语句将失败C
该语句将创建一个组合唯一索引D
该语句将创建一个组合非唯一索引
考题
单选题Examine the structure of the EMPLOYEES table: Column name Data type Remarks EMPLOYEE_ID NUMBER NOT NULL, Primary Key LAST_NAME VARCNAR2(30) FIRST_NAME VARCNAR2(30) JOB_ID NUMBER SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER You need to create an index called NAME_IDX on the first name and last name fields of the EMPLOYEES table. Which SQL statement would you use to perform this task?（）A
CREATE INDEX NAME _IDX (first_name, last_name);B
CREATE INDEX NAME _IDX (first_name, AND last_name)C
CREATE INDEX NAME_IDX ON (First_name, last_name);D
CREATE INDEX NAME_IDX ON employees (First_name, AND last_name);E
CREATE INDEX NAME_IDX ON employees (First_name, last_name);F
CREATE INDEX NAME_IDX FOR employees (First_name, last_name);
考题
判断题数据集中的数据表名称是区分大小写的，ds.Tables（"Employees"）和ds.Tables（"employees"）不是同一个表。A
对B
错
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