31.choose the best answer

Which statement is true regarding the USING clause in table joins?

A) It can be used to access data from tables through equijoins as well as nonequijoins.

B) It can be used to join tables that have columns with the same name and compatible data types.

C) It can be used to join a maximum of three tables.

D) It can be used to restrict the number of columns used in a NATURAL join.

Answer：B

(解析:using 只能用在 equiue join ，而且必须列的名字要相同，类型可以不同，但是可以隐式转过去)

【Oracle 12c】CUUG OCP认证071考试原题解析（31）的更多相关文章

  1. 【Oracle 12c】CUUG OCP认证071考试原题解析（30）

    30.choose the best answer Examine the commands used to create DEPARTMENT_DETAILS and COURSE_DETAILS: ...

  2. 【Oracle 12c】CUUG OCP认证071考试原题解析（35）

    35.choose the best answer View the Exhibit and examine the description of the EMPLOYEES table. Evalu ...

  3. 【Oracle 12c】CUUG OCP认证071考试原题解析（32）

    32.choose the best answer View the Exhibit and examine the data in EMP and DEPT tables. In the DEPT ...

  4. 【Oracle 12c】CUUG OCP认证071考试原题解析（29）

    29.choose the best answer Evaluate the following query: SQL> SELECT promo_name || q'{'s start dat ...

  5. 【12c OCP】CUUG OCP认证071考试原题解析（36）

    36.choose the best answer View the Exhibits and examine the structures of the PRODUCTS, SALES, and C ...

  6. 【12c OCP】CUUG OCP认证071考试原题解析（34）

    34.choose two View the Exhibit and examine the structure of the PRODUCT_INFORMATION and INVENTORIES ...

  7. 【12c OCP】CUUG OCP认证071考试原题解析（33）

    33.choose the best answer View the Exhibit and examine the structure of the ORDER_ITEMS table. Exami ...

  8. 【OCP认证12c题库】CUUG 071题库考试原题及答案（28）

    28.choose the best answer Evaluate the following SQL statement: SQL> SELECT promo_id, promo_categ ...

  9. 【OCP认证12c题库】CUUG 071题库考试原题及答案（27）

    27.choose two The SQL statements executed in a user session are as follows: SQL> CREATE TABLE pro ...

随机推荐

  1. 下拉菜单的实现classList.add() classList.remove() class属性的添加和删除

    <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8&quo ...

  2. docker redis

    https://www.cnblogs.com/cgpei/p/7151612.html 重启docker >systmctl restart docker >mkdir -p ~/red ...

  3. How To Manually Install Oracle Java on Ubuntu

    Introduction Java is a programming technology originally developed by Sun Microsystems and later acq ...

  4. WdatePicker.js的使用方法 帮助文档 使用说明(时间控件)

    WdatePicker.js的使用方法 帮助文档 使用说明(时间控件)   4. 日期范围限制 静态限制 注意:日期格式必须与 realDateFmt 和 realTimeFmt 一致 你可以给通过配 ...

  5. C和C++中的不定参数

    在初学C的时候,我们都会用到printf函数来写Hello World的程序.在我们看printf函数的声明时,会看到类似于下面代码 int printf(const char * __restric ...

  6. Java Thread系列（九）Master-Worker模式

    Java Thread系列(九)Master-Worker模式 Master-Worker模式是常用的并行设计模式. 一.Master-Worker 模式核心思想 Master-Worker 系统由两 ...

  7. Caffe 议事（一）：从零开始搭建 ResNet 之 残差网络结构介绍和数据准备

    声明:Caffe 系列文章是我们实验室 黄佳斌 大神所写的内部学习文档,已经获得他的授权允许. 本参考资料是在 Ubuntu14.04 版本下进行,并且默认 Caffe 所需的环境已经配置好,下面教大 ...

  8. unittest单元测试框架之coverage代码覆盖率统计

    什么是coveage? coverage是一个检测单元测试覆盖率的工具,即检查你的测试用例是否覆盖到了所有的代码.当你通过pip install coverage成功安装完coverage后,就会在p ...

  9. Redis Quick Start [熟练版]

    一.下载解压 wget http://download.redis.io/redis-stable.tar.gztar xvzf redis-stable.tar.gzcd redis-stable ...

  10. java 传参数时 类型后跟 3个点 "..." 的意义

    对照代码和运行结果便知"..." 的意义 import java.util.ArrayList; public class StringDemo { public static v ...