单选题Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?()A Define the column MAINID as NOT UPDATABLEB Define the column MAINID as a PRIMARY KEYC Define the column

题目
单选题
Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?()
A

Define the column MAINID as NOT UPDATABLE

B

Define the column MAINID as a PRIMARY KEY

C

Define the column MAINID as a FOREIGN KEY

D

Define an UPDATE trigger on table TABLEX


相似考题
参考答案和解析
正确答案: B
解析: 暂无解析
更多“单选题Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?()A Define the column MAINID as NOT UPDATABLEB Define the column MAINID as a PRIMARY KEYC Define the column ”相关问题
  • 第1题:

    What type of constraint can be used to ensure that, in any given row in a table, the value of one column never exceeds the value of another column?()

    A.Check

    B.Range

    C.Referential

    D.Informational


    参考答案:A

  • 第2题:

    What type of constraint can be used to ensure that, in any given row in a table, the value of one column never exceeds the value of another column?()

    • A、Check
    • B、Range
    • C、Referential
    • D、Informational

    正确答案:A

  • 第3题:

    You work in a company which uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 instance. There is a database named named Dworks in the instance. The Dworks table has a table named BillDetails which has a clustered primary key named BillId on the BillId column. The BillDetails table has a single XML column named GoodsDetails. The XML column has an XML index and XML data are stored in this XML column. A new column named GoodsID is added to the BillDetails table. GoodsID must be included in the primary key.  So what action should you perform to achieve this goal?()  

    • A、You should drop the XML index on the table. Modify the primary key. Recreate the XML index 
    • B、You should alter the XML index and set the ALLOW_ROW_LOCKS = OFF option. Alter the primary key and set the ALLOW_ROW_LOCKS = ON option. 
    • C、You should move the XML data to a temporary table. Clear the XML data from the original table by setting the GoodsDetails column to NULL. Modify the primary key. Repopulate the ProductSpecs column. 
    • D、You should disable the XML index on the GoodsDetails column. Modify the primary key.Enable the XML index on the ProductSpecs column.

    正确答案:A

  • 第4题:

    GEM机箱的地址插板从下往上依次作用是()

    • A、Row,notused,Column,MagazineAddress
    • B、Row,Column,notused,MagazineAddress
    • C、Column,Row,notused,MagazineAddress
    • D、notused,Row,Column,MagazineAddress

    正确答案:A

  • 第5题:

    When defining a referential constraint between the parent table T2 and the dependent table T1, which of the following is true?()

    • A、The list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.
    • B、The list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.
    • C、The list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.
    • D、The list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.

    正确答案:C

  • 第6题:

    Which statement describes the effect on an index, when the indexed column for the rows is updatedin the base table()

    • A、An update in a leaf row takes place.
    • B、The index becomes invalid after the update.
    • C、The leaf block containing the row to be updated is marked as invalid.
    • D、A row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted

    正确答案:D

  • 第7题:

    Which two statements are true when row archival management is enabled?()

    • A、The ORA_ARCHIVE_STATE column visibility is controlled by the ROW ARCHIVAL VISIBILITY session parameter.
    • B、The ORA_ARCHIVE_STATE column is updated manually or by a program that could reference activity tracking columns, to indicate that a row is no longer considered active.
    • C、The ROW ARCHIVAL VISIBILITY session parameter defaults to active rows only.
    • D、The ORA_ARCHIVE_STATE column is visible if referenced in the select list of a query.
    • E、The ORA_ARCHIVE_STATE column is updated automatically by the Oracle Server based on activity tracking columns, to Indicate that a row is no longer considered active.

    正确答案:A,B

  • 第8题:

    The SCOTT user has an index on the ITEM_DESC column of the ITEM table. As part of the year-ending task, SCOTT updates the ITEM_DESC column for most of the rows in the ITEM table. How does this change to the table affect the index?()

    • A、An update in a leaf row takes place.
    • B、The index becomes invalid after the update.
    • C、The leaf block containing the row to be updated is marked as invalid.
    • D、A row in the leaf block of the index for the key value is deleted and inserted.

    正确答案:D

  • 第9题:

    单选题
    Which of the following scenarios will ensure that the value of the NEXT_STEPNO column in a given row of table TABLEX exists as a value of column STEPNO (usually in another row) in the same table?()
    A

    Define a UNIQUE constraint on the columns NEXT_STEPNO and STEPNO.

    B

    Define a CHECK constraint on the NEXT_STEPNO column (NEXT_STEPNO = STEPNO).

    C

    Define column STEPNO as the primary key of TABLEX and column NEXT_STEPNO as a foreign key referencing column STEPNO of the same table.

    D

    Define column NEXT_STEPNO as the primary key of TABLEX and column STEPNO as a foreign key referencing column NEXT_STEPNO in the same table.


    正确答案: A
    解析: 暂无解析

  • 第10题:

    单选题
    Which statement describes the effect on an index, when the indexed column for the rows is updatedin the base table()
    A

    An update in a leaf row takes place.

    B

    The index becomes invalid after the update.

    C

    The leaf block containing the row to be updated is marked as invalid.

    D

    A row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted


    正确答案: B
    解析: 暂无解析

  • 第11题:

    单选题
    You work in a company which uses SQL Server 2008. You are the administrator of the company database. Now you are in charge of a SQL Server 2008 instance. There is a database named named Dworks in the instance. The Dworks table has a table named BillDetails which has a clustered primary key named BillId on the BillId column. The BillDetails table has a single XML column named GoodsDetails. The XML column has an XML index and XML data are stored in this XML column. A new column named GoodsID is added to the BillDetails table. GoodsID must be included in the primary key.  So what action should you perform to achieve this goal?()
    A

    You should drop the XML index on the table. Modify the primary key. Recreate the XML index 

    B

    You should alter the XML index and set the ALLOW_ROW_LOCKS = OFF option. Alter the primary key and set the ALLOW_ROW_LOCKS = ON option. 

    C

    You should move the XML data to a temporary table. Clear the XML data from the original table by setting the GoodsDetails column to NULL. Modify the primary key. Repopulate the ProductSpecs column. 

    D

    You should disable the XML index on the GoodsDetails column. Modify the primary key.Enable the XML index on the ProductSpecs column.


    正确答案: A
    解析: 暂无解析

  • 第12题:

    单选题
    Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?()
    A

    Define the column MAINID as NOT UPDATABLE

    B

    Define the column MAINID as a PRIMARY KEY

    C

    Define the column MAINID as a FOREIGN KEY

    D

    Define an UPDATE trigger on table TABLEX


    正确答案: D
    解析: 暂无解析

  • 第13题:

    Click the Exhibit button and examine the data in the EMPLOYEES table.On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID column is a NOT NULL column.Evaluate this DELETE statement:DELETE employee_id, salary, job_idFROM employeesWHERE dept_id = 90;Why does the DELETE statement fail when you execute it?()

    A.There is no row with dept_id 90 in the EMPLOYEES table.

    B.You cannot delete the JOB_ID column because it is a NOT NULL column.

    C.You cannot specify column names in the DELETE clause of the DELETE statement.

    D.You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.


    参考答案:C

  • 第14题:

    Which of the following scenarios will ensure that the value of the NEXT_STEPNO column in a given row of table TABLEX exists as a value of column STEPNO (usually in another row) in the same table?()

    • A、Define a UNIQUE constraint on the columns NEXT_STEPNO and STEPNO.
    • B、Define a CHECK constraint on the NEXT_STEPNO column (NEXT_STEPNO = STEPNO).
    • C、Define column STEPNO as the primary key of TABLEX and column NEXT_STEPNO as a foreign key referencing column STEPNO of the same table.
    • D、Define column NEXT_STEPNO as the primary key of TABLEX and column STEPNO as a foreign key referencing column NEXT_STEPNO in the same table.

    正确答案:C

  • 第15题:

    What type of constraint is used to ensure that each row inserted into the EMPLOYEE table with a value in the WORKDEPT column has a row with a corresponding value in the DEPTNO column of the DEPARTMENT table?()

    • A、A check constraint on the EMPLOYEE table
    • B、A unique constraint on the EMPLOYEE table WORKDEPT column
    • C、A foreign key reference from the DEPARTMENT tables DEPTNO column to the WORKDEPT column of the EMPLOYEE table
    • D、A foreign key reference from the EMPLOYEE tables WORKDEPT column to the DEPTNO column of the DEPARTMENT table

    正确答案:D

  • 第16题:

    Which of the following can be used to ensure that once a row has been inserted in table TABLEX, the column MAINID in that row cannot be updated?()

    • A、Define the column MAINID as NOT UPDATABLE
    • B、Define the column MAINID as a PRIMARY KEY
    • C、Define the column MAINID as a FOREIGN KEY
    • D、Define an UPDATE trigger on table TABLEX

    正确答案:D

  • 第17题:

    Which two are true about aggregate functions? ()

    • A、You can use aggregate functions in any clause of a SELECT statement.
    • B、You can use aggregate functions only in the column list of the select clause and in the WHERE clause of a SELECT statement.
    • C、You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.
    • D、You can pass column names, expressions, constants, or functions as parameter to an aggregate function.
    • E、You can use aggregate functions on a table, only by grouping the whole table as one single group.
    • F、You cannot group the rows of a table by more than one column while using aggregate functions.

    正确答案:A,D

  • 第18题:

    Examine the following command: CREATE TABLE (prod_id number(4), Prod_name varchar2 (20), Category_id number(30), Quantity_on_hand number (3) INVISIBLE); Which three statements are true about using an invisible column in the PRODUCTS table?()

    • A、The %ROWTYPE attribute declarations in PL/SQL to access a row will not display the invisible column in the output.
    • B、The DESCRIBE commands in SQL *Plus will not display the invisible column in the output.
    • C、Referential integrity constraint cannot be set on the invisible column.
    • D、The invisible column cannot be made visible and can only be marked as unused.
    • E、A primary key constraint can be added on the invisible column.

    正确答案:A,B,C

  • 第19题:

    You execute the following PL/SQL:Which two statements are true?()

    • A、Fine-Grained Auditing (FGA) is enabled for the PRICE column in the PRODUCTS table for SELECT statements only when a row with PRICE > 10000 is accessed.
    • B、FGA is enabled for the PRODUCTS.PRICE column and an audit record is written whenever a row with PRICE > 10000 is accessed.
    • C、FGA is enabled for all DML operations by JIM on the PRODUCTS.PRICE column.
    • D、FGA is enabled for the PRICE column of the PRODUCTS table and the SQL statements is captured in the FGA audit trial.

    正确答案:A,B

  • 第20题:

    You are modifying a table named Product in a SQL Server 2005 database. You want to add a new column named FriendlyName to the Product table. A friendly name for each product will be stored in this column. The table currently contains data. The sales department has not yet created a friendly name for each product. FriendlyName is a required value for each product. You want to add this new column by using the least amount of effort. What should you do?()

    • A、Define the new column as NULL.Update the FriendlyName column to the same value as the productName column. Alter the FriendlyName column to be NOT NULL.
    • B、Define the new column as NOT NULL with a default value of ’Undefined.’
    • C、Define the new column as NULL. Use application logic to enforce the data constraint.
    • D、Define the new column as NULL with a default value of ’Undefined.’

    正确答案:B

  • 第21题:

    单选题
    What type of constraint can be used to ensure that, in any given row in a table, the value of one column never exceeds the value of another column?()
    A

    Check

    B

    Range

    C

    Referential

    D

    Informational


    正确答案: D
    解析: 暂无解析

  • 第22题:

    单选题
    The SCOTT user has an index on the ITEM_DESC column of the ITEM table. As part of the year-ending task, SCOTT updates the ITEM_DESC column for most of the rows in the ITEM table. How does this change to the table affect the index?()
    A

    An update in a leaf row takes place.

    B

    The index becomes invalid after the update.

    C

    The leaf block containing the row to be updated is marked as invalid.

    D

    A row in the leaf block of the index for the key value is deleted and inserted.


    正确答案: B
    解析: 暂无解析

  • 第23题:

    多选题
    Which two statements are true when row archival management is enabled?()
    A

    The ORA_ARCHIVE_STATE column visibility is controlled by the ROW ARCHIVAL VISIBILITY session parameter.

    B

    The ORA_ARCHIVE_STATE column is updated manually or by a program that could reference activity tracking columns, to indicate that a row is no longer considered active.

    C

    The ROW ARCHIVAL VISIBILITY session parameter defaults to active rows only.

    D

    The ORA_ARCHIVE_STATE column is visible if referenced in the select list of a query.

    E

    The ORA_ARCHIVE_STATE column is updated automatically by the Oracle Server based on activity tracking columns, to Indicate that a row is no longer considered active.


    正确答案: A,B
    解析: 暂无解析

  • 第24题:

    单选题
    What type of constraint is used to ensure that each row inserted into the EMPLOYEE table with a value in the WORKDEPT column has a row with a corresponding value in the DEPTNO column of the DEPARTMENT table?()
    A

    A check constraint on the EMPLOYEE table

    B

    A unique constraint on the EMPLOYEE table WORKDEPT column

    C

    A foreign key reference from the DEPARTMENT tables DEPTNO column to the WORKDEPT column of the EMPLOYEE table

    D

    A foreign key reference from the EMPLOYEE tables WORKDEPT column to the DEPTNO column of the DEPARTMENT table


    正确答案: C
    解析: 暂无解析