Examine the following statement that is used to modify the primary key constraint on the SALES tabl
来源：互联网 发布：求购淘宝店 编辑：程序博客网 时间：2024/05/29 09:20
Examine the following statement that is used to modify the primary key constraint on theSALES table:SQL> ALTER TABLE SALES MODIFY CONSTRAINT pk DISABLE VALIDATE;Which three statements are true regarding the above command? (Choose three.)选项A.The constraint remains valid.B.The index on the constraint is dropped.C.It allows the loading of data into the table using SQL *Loader.D.New data conforms to the constraint, but existing data is not checked.E.It allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.
Correct Answers: A B
【考点分析】约束的DISABLE VALIDATE属性
【题意简述】把表的主键约束修改为DISABLE VALIDATE,描述正确的是?
【答案剖析】.
A: 正确, DISABLE VALIDATE的约束是有效的
B: 正确,主键约束会自动维护一个唯一性索引,约束enable,索引在,disable,索引不在
C: 错误, DISABLE VALIDATE不允许做DML操作,无法导入数据
D: 错误, DISABLE VALIDATE的约束对已有数据校验,新数据不校验,说反了 E: 错误,不允许做INSERT/UPDATE/DELETE DML操作
- Examine the following statement that is used to modify the primary key constraint on the SALES tabl
- 10.Examine the following statement that is used to modify the constraint on the SALES table:
- 183 Examine the following command that is used to duplicate a database on the same host: RMAN> RUN {
- 156.Examine the following steps performed on a database instance: 1: The DBA grants the CREATE TABL
- 164.Examine the command that is used to create a table: SQL> CREATE TABLE orders( oid NUMBER(6) PRI
- 161 Examine the following command used to perform incremental level 0 backup: RMAN> BACKUP INCREMENT
- 86.View the Exhibit to examine the output for the CROSSCHECK BACKUP command. Which statement is true
- 40.View the Exhibit to examine the description for the SALES and PRODUCTS tables.
- 188 Examine the following scenario: The target database instance is running. The most recent backup
- 2 Which of the following cannot be used as input to the SQL Tuning Advisor? (Choose all that apply.)
- The report server cannot decrypt the symmetric key that is used to access sensitive or encrypted data in a report server databas
- 171.View the Exhibit and examine the command used to create the ZONEDATA table.
- You execute the following command to change the status of the SALES tablespace: SQL> ALTER TABLESPAC
- 36.Examine the following SQL commands:
- 2.View the Exhibit to examine the description for the SALES table. Which views can have all DML oper
- Saving changes is not permitted. The changes that you have made require the following tables to be d
- Unable to parse constraint format: tabelView is not a key in the views dict
- The ALTER TABLE statement conflicted with the FOREIGN KEY constraint "FK_SortId".
- 常见指针错误
- css网站
- Android MVC模式你真的明白了吗？？
- Android SDK与源码下载
- stringify这个函数是什么缩写？
- Examine the following statement that is used to modify the primary key constraint on the SALES tabl
- Java继承和多态=== Java Object类
- Ubuntu在终端中安装和卸载软件的方法
- 一起故障引发的线上MySQL数据库权限分级以及数据库实例大小限制
- 字符串流 istringstream 和 ostringstream 的用法
- Core Image
- iOS,数据库的使用（FMDB库的使用和配置）
- 快速排序
- str_replace中的匹配空白符，必须用双引号
