考虑如下数据表和查询，如何添加索引功能提高查询速度?( )Create table mytable(Id int,Name char(100),Address1 varchar(100),Address2 varchar(100),Zipcode varshar(10),Sity varchar(50),Province varchar(2))Select id, varcharFrom mytableWheA.给Zipcode添加全文的索引B.给Name添加索引C.给Id添加索引，然后给Name和Zip

题目

考虑如下数据表和查询，如何添加索引功能提高查询速度?( )Create table mytable(Id int,Name char(100),Address1 varchar(100),Address2 varchar(100),Zipcode varshar(10),Sity varchar(50),Province varchar(2))Select id, varcharFrom mytableWhe

A.给Zipcode添加全文的索引

B.给Name添加索引

C.给Id添加索引，然后给Name和Zipcode分别添加索引

D.给id添加索引

相似考题

1.Examine the structure of the EMP_DEPT_VU view:Column Name Type RemarksEMPLOYEE_ID NUMBER From the EMPLOYEES tableEMP_NAME VARCHAR2(30) From the EMPLOYEES table JOB_ID VARCHAR2(20) From the EMPLOYEES tableSALARY NUMBER From the EMPLOYEES tableDEPARTMENT_ID NUMBER From the DEPARTMENTS table DEPT_NAME VARCHAR2(30) From the DEPARTMENTS table Which SQL statement produces an error?（）A. SELECT * FROM emp_dept_vu;B. SELECT department_id, SUM(salary) FROM emp_dept_vu GROUP BY department _ id;C. SELECT department_id, job_id, AVG(salary) FROM emp_dept_vu GROUP BY department _ id, job_id;D. SELECT job_id, SUM(salary) FROM emp_dept_vu WHERE department_id IN (10,20) GROUP BY job_id HAVING SUM (salary) > 20000E. None of the statements produce an error; all are valid.

2.Examine the structure of the EMPLOYEES and DEPARTMENTS tables:EMPLOYEESEMPLOYEE_ID NUMBERDEPARTMENT_ID NUMBERMANAGER_ID NUMBERLAST_NAME VARCHAR2(25)DEPARTMENTSDEPARTMENT_ID NUMBERMANAGER_ID NUMBERDEPARTMENT_NAME VARCHAR2(35)LOCATION_ID NUMBERYou want to create a report displaying employee last names, department names, and locations. Which query should you use to create an equi-join?（）A. SELECT last_name, department_name, location_id FROM employees , department ;B. SELECT employees.last_name, departments.department_name, departments.location_id FROM employees e, departments D WHERE e.department_id = d.department_id;C. SELECT e.last_name, d.department_name, d.location_id FROM employees e, departments D WHERE manager_id = manager_id;D. SELECT e.last_name, d.department_name, d.location_id FROM employees e, departments D WHERE e.department_id = d.department_id;

3.The EMPLOYEES table contains these columns:EMPLOYEE_ID NUMBER(4)LAST_NAME VARCHAR2 (25)JOB_ID VARCHAR2(10)You want to search for strings that contain ‘SA_‘ in the JOB_ID column. Which SQL statement do you use?（）A. SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE ‘%SA\_%‘ESCAPE‘\‘;B. SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE ‘%SA_‘;C. SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE ‘%SA_‘ESCAPE‘\‘;D. SELECT employee_id, last_name, job_id FROM employees WHERE job_id ‘%SA_‘;

4.You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns:CUST_ID NUMBER(4) NOT NULLCUST_NAME VARCHAR2(100) NOT NULLCUST_ADDRESS VARCHAR2(150)CUST_PHONE VARCHAR2(20)Which SELECT statement accomplishes this task?（）A. SELECT* FROM customers;B. SELECT name, address FROM customers;C. SELECT id, name, address, phone FROM customers;D. SELECT cust_name, cust_address FROM customers;E. SELECT cust_id, cust_name, cust_address, cust_phone FROM customers;

参考答案和解析
参考答案：B
更多“考虑如下数据表和查询，如何添加索引功能提高查询速度?( )Create table mytable(Id int,Name char(100),Address1 varchar(100),Address2 varchar(100),Zipcode varshar(10),Sity varchar(50),Province varchar(2))Select id, varcharFrom mytableWheA.给Zipcode添加全文的索引B.给Name添加索引C.给Id添加索引，然后给Name和Zip”相关问题

  • 第1题：

    You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns: CUST_ID NUMBER(4) NOT NULL CUST_NAME VARCHAR2(100) NOT NULL CUST_ADDRESS VARCHAR2(150) CUST_PHONE VARCHAR2(20) Which SELECT statement accomplishes this task?（）

    • A、SELECT* FROM customers;
    • B、SELECT name, address FROM customers;
    • C、SELECT id, name, address, phone FROM customers;
    • D、SELECT cust_name, cust_address FROM customers;
    • E、SELECT cust_id, cust_name, cust_address, cust_phone FROM customers;

    正确答案:D

  • 第2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

    正确答案:D

  • 第3题：

    现有表Employee，字段：id（int）、firstname（varchar）、lastname（varchar）；以下sql语句错误的是（）

    • A、select firstname+’.’+lastnameas’name’from employee
    • B、select firstname+’.’+lastname=’name’from employee
    • C、select’name’=firstname+’.’+lastnamefrom employee
    • D、select firstname，lastname from employee

    正确答案:B

  • 第4题：

    The EMPLOYEES table contains these columns: EMPLOYEE_ID NUMBER(4) LAST_NAME VARCHAR2 (25) JOB_ID VARCHAR2(10) You want to search for strings that contain 'SA_' in the JOB_ID column. Which SQL statement do you use?（）

    • A、SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA/_%' ESCAPE '/';
    • B、SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA_';
    • C、SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA_' ESCAPE "/";
    • D、SELECT employee_id, last_name, job_id FROM employees WHERE job_id = '%SA_';

    正确答案:A

  • 第5题：

    You executed the following code：   SQL> CERATE TABLE COUNTRY   （COUNTRY_ID CHAR（2） CONSTRAINT COUNTRY_ID_nn NOT NULL，   COUNTRY_NAME VARCHAR2（20），   CURRENCY_NAME VARCHAR2（20），   CONSTRAINT COUNTRY_ID_PK PRIMARY KEY （COUNTRY_ID））   ORGANIZATION INDEX；   Which types of tables will be created automatically？（）

    • A、 journal table
    • B、 clustered table
    • C、 mapping table
    • D、 partitioned table

    正确答案:C

  • 第6题：

    The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) Which statement finds the rows in the CUSTOMERS table that do not have a postal code? （）

    • A、SELECT customer_id, customer_name FROM customers WHERE postal_code CONTAINS NULL;
    • B、SELECT customer_id, customer_name FROM customers WHER postal_code = ' ___________';
    • C、SELECT customer_id, customer_name FROM customers WHERE postal _ code IS NULL;
    • D、SELECT customer_id, customer_name FROM customers WHERE postal code IS NVL;
    • E、SELECT customer_id, customer_name FROM customers WHERE postal_code = NULL;

    正确答案:C

  • 第7题：

    Examine the structure of the EMP_DEPT_VU view: Column Name Type Remarks EMPLOYEE_ID NUMBER From the EMPLOYEES table EMP_NAME VARCHAR2(30) From the EMPLOYEES table JOB_ID VARCHAR2(20) From the EMPLOYEES table SALARY NUMBER From the EMPLOYEES table DEPARTMENT_ID NUMBER From the DEPARTMENTS table DEPT_NAME VARCHAR2(30) From the DEPARTMENTS table Which SQL statement produces an error?（）

    • A、SELECT * FROM emp_dept_vu;
    • B、SELECT department_id, SUM(salary) FROM emp_dept_vu GROUP BY department _ id;
    • C、SELECT department_id, job_id, AVG(salary) FROM emp_dept_vu GROUP BY department _ id, job_id;
    • D、SELECT job_id, SUM(salary) FROM emp_dept_vu WHERE department_id IN (10,20) GROUP BY job_id HAVING SUM (salary) > 20000
    • E、None of the statements produce an error; all are valid.

    正确答案:E

  • 第8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


    正确答案： C
    解析： 暂无解析

  • 第9题：

    单选题
    You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns: CUST_ID NUMBER(4) NOT NULL CUST_NAME VARCHAR2(100) NOT NULL CUST_ADDRESS VARCHAR2(150) CUST_PHONE VARCHAR2(20) Which SELECT statement accomplishes this task?（）
    A

    SELECT* FROM customers;

    B

    SELECT name, address FROM customers;

    C

    SELECT id, name, address, phone FROM customers;

    D

    SELECT cust_name, cust_address FROM customers;

    E

    SELECT cust_id, cust_name, cust_address, cust_phone FROM customers;


    正确答案： C
    解析： 暂无解析

  • 第10题：

    单选题
    The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) The CUSTOMER_ID column is the primary key for the table. You need to determine how dispersed your customer base is. Which expression finds the number of different countries represented in the CUSTOMERS table?（）
    A

    COUNT(UPPER(country_address))

    B

    COUNT(DIFF(UPPER(country_address)))

    C

    COUNT(UNIQUE(UPPER(country_address)))

    D

    COUNT DISTINCT UPPER(country_address)

    E

    COUNT(DISTINCT (UPPER(country_address)))


    正确答案： A
    解析： 暂无解析

  • 第11题：

    单选题
    在Products数据库中建立一个新表Authors，表中应该包含name列和每个作者的ID列，下列语法正确的是（）。
    A

    CREATE TABLE AUTHORS ON Prpducts(name varchar(50),IDsmallint)

    B

    ALTER DATABASE products ADD TABLE Authors(name varchar(50),IDsmallint)

    C

    CREATE TABLE Products.Authors(name varchar(50),IDsmallint)

    D

    Create TABLE Products.Authors(name,ID)


    正确答案： A
    解析： 暂无解析

  • 第12题：

    单选题
    You executed the following code：   SQL> CERATE TABLE COUNTRY   （COUNTRY_ID CHAR（2） CONSTRAINT COUNTRY_ID_nn NOT NULL，   COUNTRY_NAME VARCHAR2（20），   CURRENCY_NAME VARCHAR2（20），   CONSTRAINT COUNTRY_ID_PK PRIMARY KEY （COUNTRY_ID））   ORGANIZATION INDEX；   Which types of tables will be created automatically？（）
    A

     journal table

    B

     clustered table

    C

     mapping table

    D

     partitioned table


    正确答案： A
    解析： 暂无解析

  • 第13题：

    You executed the following code：   SQL> CREATE TABLE COUNTRY   （COUNTRY_ID CHAR（2） CONSTRAINT COUNTRY_ID_nn NOT NULL，   COUNTRY_NAME VARCHAR2（20），   CURRENCY_NAME VARCHAR2（20），   CONSTRAINT COUNTRY_ID_PK PRIMARY KEY （COUNTRY_ID））   ORGANIZATION INDEX；   In which tablespace will the mapping table be created？（）

    • A、 SYSTEM tablespace
    • B、 SYSAUX tablespace
    • C、 Undo tablespace
    • D、 The tablespace of the Index Organized Table （IOT）

    正确答案:D

  • 第14题：

    在Products数据库中建立一个新表Authors，表中应该包含name列和每个作者的ID列，下列语法正确的是（）。

    • A、CREATE TABLE AUTHORS ON Prpducts(name varchar(50),IDsmallint)
    • B、ALTER DATABASE products ADD TABLE Authors(name varchar(50),IDsmallint)
    • C、CREATE TABLE Products.Authors(name varchar(50),IDsmallint)
    • D、Create TABLE Products.Authors(name,ID)

    正确答案:C

  • 第15题：

    The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) The CUSTOMER_ID column is the primary key for the table. Which two statements find the number of customers? （）

    • A、SELECT TOTAL(*) FROM customer;
    • B、SELECT COUNT(*) FROM customer;
    • C、SELECT TOTAL(customer_id) FROM customer;
    • D、SELECT COUNT(customer_id) FROM customer;
    • E、SELECT COUNT(customers) FROM customer;
    • F、SELECT TOTAL(customer_name) FROM customer;

    正确答案:B,D

  • 第16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';

    正确答案:D

  • 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 name = 'carrey');

    正确答案:C

  • 第18题：

    Examine the description of the CUSTOMERS table: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) The CUSTOMER_ID column is the primary key for the table. Which statement returns the city address and the number of customers in the cities Los Angeles or San Francisco?（）

    • A、SELECT city_address, COUNT(*) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco');
    • B、SELECT city_address, COUNT(*) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco') GROUP BY city_address;
    • C、SELECT city_address, COUNT(customer_id) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco') GROUP BY city_address, customer_id;
    • D、SELECT city_address, COUNT(customer_id) FROM customers GROUP BY city_address IN ('Los Angeles', 'San Francisco');

    正确答案:B

  • 第19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');

    正确答案:C

  • 第20题：

    多选题
    The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) The CUSTOMER_ID column is the primary key for the table. Which two statements find the number of customers?（）
    A

    SELECT TOTAL(*) FROM customer;

    B

    SELECT COUNT(*) FROM customer;

    C

    SELECT TOTAL(customer_id) FROM customer;

    D

    SELECT COUNT(customer_id) FROM customer;

    E

    SELECT COUNT(customers) FROM customer;

    F

    SELECT TOTAL(customer_name) FROM customer;


    正确答案： A,F
    解析： 暂无解析

  • 第21题：

    单选题
    You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns: CUST_ID NUMBER(4) NOT NULL CUST_NAME VARCHAR2(100) NOT NULL CUST_ADDRESS VARCHAR2(150) CUST_PHONE VARCHAR2(20) Which SELECT statement accomplishes this task?（）
    A

    SELECT* FROM customers;

    B

    SELECT name, address FROM customers;

    C

    SELECT id, name, address, phone FROM customers;

    D

    SELECT cust_name, cust_address FROM customers;

    E

    SELECT cust_id, cust_name, cust_address, cust_phone FROM customers;


    正确答案： E
    解析： 暂无解析

  • 第22题：

    单选题
    The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) Which statement finds the rows in the CUSTOMERS table that do not have a postal code? （）
    A

    SELECT customer_id, customer_name FROM customers WHERE postal_code CONTAINS NULL;

    B

    SELECT customer_id, customer_name FROM customers WHER postal_code = ' ___________';

    C

    SELECT customer_id, customer_name FROM customers WHERE postal _ code IS NULL;

    D

    SELECT customer_id, customer_name FROM customers WHERE postal code IS NVL;

    E

    SELECT customer_id, customer_name FROM customers WHERE postal_code = NULL;


    正确答案： A
    解析： 暂无解析

  • 第23题：

    单选题
    You executed the following code：   SQL> CREATE TABLE COUNTRY   （COUNTRY_ID CHAR（2） CONSTRAINT COUNTRY_ID_nn NOT NULL，   COUNTRY_NAME VARCHAR2（20），   CURRENCY_NAME VARCHAR2（20），   CONSTRAINT COUNTRY_ID_PK PRIMARY KEY （COUNTRY_ID））   ORGANIZATION INDEX；   In which tablespace will the mapping table be created？（）
    A

     SYSTEM tablespace

    B

     SYSAUX tablespace

    C

     Undo tablespace

    D

     The tablespace of the Index Organized Table （IOT）


    正确答案： D
    解析： 暂无解析

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