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?()ADefine the column MAINID as NOT UPDATABLEBDefine the column MAINID as a PRIMARY KEYCDefine the column MAINID as a FOREIGN KEYDDefine an UPDATE trigger on table TABLEX

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


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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 tableB.A unique constraint on the EMPLOYEE table WORKDEPT columnC.A foreign key reference from the DEPARTMENT tables DEPTNO column to the WORKDEPT column of the EMPLOYEE tableD.A foreign key reference from the EMPLOYEE tables WORKDEPT column to the DEPTNO column of the DEPARTMENT table

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.

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 MAINID as a FOREIGN KEYD.Define an UPDATE trigger on table TABLEX

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.CheckB.RangeC.ReferentialD.Informational

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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.

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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 tableB、A unique constraint on the EMPLOYEE table WORKDEPT columnC、A foreign key reference from the DEPARTMENT tables DEPTNO column to the WORKDEPT column of the EMPLOYEE tableD、A foreign key reference from the EMPLOYEE tables WORKDEPT column to the DEPTNO column of the DEPARTMENT table

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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 MAINID as a FOREIGN KEYD、Define an UPDATE trigger on table TABLEX

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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.

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.’

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?()ADefine a UNIQUE constraint on the columns NEXT_STEPNO and STEPNO.BDefine a CHECK constraint on the NEXT_STEPNO column (NEXT_STEPNO = STEPNO).CDefine column STEPNO as the primary key of TABLEX and column NEXT_STEPNO as a foreign key referencing column STEPNO of the same table.DDefine column NEXT_STEPNO as the primary key of TABLEX and column STEPNO as a foreign key referencing column NEXT_STEPNO in the same table.

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?()ACheckBRangeCReferentialDInformational

单选题Which statement describes the effect on an index, when the indexed column for the rows is updatedin the base table()AAn update in a leaf row takes place.BThe index becomes invalid after the update.CThe leaf block containing the row to be updated is marked as invalid.DA row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted

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?()AAn update in a leaf row takes place.BThe index becomes invalid after the update.CThe leaf block containing the row to be updated is marked as invalid.DA row in the leaf block of the index for the key value is deleted and inserted.

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?()AYou should drop the XML index on the table. Modify the primary key. Recreate the XML index BYou 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. CYou 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. DYou should disable the XML index on the GoodsDetails column. Modify the primary key.Enable the XML index on the ProductSpecs column.

多选题Which two statements are true when row archival management is enabled?()AThe ORA_ARCHIVE_STATE column visibility is controlled by the ROW ARCHIVAL VISIBILITY session parameter.BThe 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.CThe ROW ARCHIVAL VISIBILITY session parameter defaults to active rows only.DThe ORA_ARCHIVE_STATE column is visible if referenced in the select list of a query.EThe 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.

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?()ADefine the column MAINID as NOT UPDATABLEBDefine the column MAINID as a PRIMARY KEYCDefine the column MAINID as a FOREIGN KEYDDefine an UPDATE trigger on table TABLEX

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?()AA check constraint on the EMPLOYEE tableBA unique constraint on the EMPLOYEE table WORKDEPT columnCA foreign key reference from the DEPARTMENT tables DEPTNO column to the WORKDEPT column of the EMPLOYEE tableDA foreign key reference from the EMPLOYEE tables WORKDEPT column to the DEPTNO column of the DEPARTMENT table