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多选题You plan to move data from a flat file to a table in your database. You decide to use SQL*Loader direct pathload method to perform this task. The table in which you plan to load data is an important table having variousintegrity constraints defined on 

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多选题
You plan to move data from a flat file to a table in your database. You decide to use SQL*Loader direct pathload method to perform this task. The table in which you plan to load data is an important table having variousintegrity constraints defined on it.  Which constraints will remain enabled by default during this operation()
A

CHECK

B

UNIQUE

C

NOT NULL

D

PRIMARY KEY

E

FOREIGN KEY

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相似问题和答案

第1题:

You are the administrator of a SQL Server 2000 computer. You are creating a data transformation services package. As the first step in this process, you need to load data from text files into a database table. These text files contain data on new stores that join your franchise. The text files list the data columns in the following format StoreID, StoreName, Address, City, State, PostalCode, ManagerID, StoreTypeID, FacilityID.

The destination table is configured as shown in the exhibit.

You want to load the data into the table as quickly as possible. What should you do?

A.Use a Bulk Insert Task to read the data into a temporary table. Use an Execute SQL task to import the appropriate data into the destination table.

B.Create and edit a format file to select the columns you want to import. Use a Bulk Insert Task, and then specify the format file to import the appropriate data into the destination table.

C.Use a transform. data task to import the data. Use Microsoft ActiveX transformation scripts to write the appropriate data to the appropriate columns in the destination table.

D.Create and edit a format file to select the columns you want to import. Use a transform. data task, and then specify the format file to import the appropriate data into the destination table.


正确答案:B
解析:Explanation:TheBulkInsertTaskisthefastestmechanismforcopyinglargeamountsofdataintoaSQLServer2000tableorview.However,transformationscannotbeperformedonthedatawhileitismovedfromthesourcefiletothetableorview,asthiswouldslowdownthedatacopyprocess.ThusthetextfilemustbeformattedbeforetheBulkInsertTaskisused.TheformatfileprovidesthedefaultinformationusedeithertobulkcopythedatainthedatafileintoaninstanceofSQLServer2000ortobulkcopydataoutfromthetable.TheformatfilealsoprovidesawaytobulkcopydataselectivelyfromadatafiletoaninstanceofSQLServer.Thisallowsforthetransferofdatatoatablewhenthereisamismatchbetweenfieldsinthedatafileandcolumnsinthetable.Byusingaformatfile,itispossibletobulkcopydataintoaninstanceofSQLServerwithouthavingtoaddordeleteunnecessarydata,orreorderexistingdata,inthedatafile.IncorrectAnswers:A:TheBulkInsertTaskisthefastestmechanismforcopyinglargeamountsofdataintoaSQLServer2000tableorview.Itcanmakeuseofaformatfilethatallowsforthetransferofdatatoatablewhenthereisamismatchbetweenfieldsinthedatafileandcolumnsinthetable.Byusingaformatfile,itispossibletobulkcopydataintoaninstanceofSQLServerwithouthavingtoaddordeleteunnecessarydata,orreorderexistingdata,inthedatafile.Itthusmakestheneedtofirstimportthedataintoatemporarytableobsolete.C:TheTransform.Datataskisusedtocopydatabetweenasourceanddestinationandtooptionallyapplycolumn-leveltransformationstothedata.TheTransform.DatataskisthemostbasicimplementationofthedatapumpengineinDataTransformationServices(DTS)andisoptimizedforinsert-basedcopyingandtransformingofcolumn-leveldatabetweencommercialdatabases,spreadsheets,andtextfiles.However,theBulkInserttaskprovidesthebestperformanceforbulkinsertingtextfilesintoSQLServer2000,althoughitcannotbeusedtotransform.data.D:TheBulkInsertTaskisthefastestmechanismforcopyinglargeamountsofdataintoaSQLServer2000tableorview.Itcanmakeuseofaformatfilethatallowsforthetransferofdatatoatablewhenthereisamismatchbetweenfieldsinthedatafileandcolumnsinthetable.Byusingaformatfile,itispossibletobulkcopydataintoaninstanceofSQLServerwithouthavingtoaddordeleteunnecessarydata,orreorderexistingdata,inthedatafile.

第2题:

A data file became corrupted in your database due to bad sectors on the disk. Because of corruption, you lost all the important tables in that data file. Which method would you use for recovery?()

  • A、flash back all the tables in the data file, one by one
  • B、restore the data file to a new location and perform a media recovery
  • C、flash back the database; there is no need to restore the data file
  • D、restore the data file from the most recent backup and flash back the database

正确答案:B

第3题:

You are the database administrator for a retail company. The company owns 270 stores. Every month, each store submits approximately 2,000 sales records, which are loaded into a SQL Server 2000 database at the corporate headquarters.

A Data Transformation Services (DTS) package transforms the sales records, as they are loaded. The package writes the transformed sales records to the Sales table, which has a column for integer primary key values. The IDENTITY property automatically assigns a key value to each transformed sales record.

After loading this month's sales data, you discover that a portion of the data contains errors. You stop loading data, identify the problem records, and delete those records from the database.

You want to reuse the key values that were assigned to the records that you deleted. You want to assign the deleted key values to the next sales records you load. You also want to disrupt users' work as little as possible.

What should you do?

A.Export all records from the Sales table to a temporary table. Truncate the Sales table, and then reload the records from the temporary table.

B.Export all records from the Sales table to a text file. Drop the Sales table, and then reload the records from the text file.

C.Use the DBCC CHECKIDENT statement to reseed the Sales table's IDENTITY property.

D.Set the Sales table's IDENTITY_INSERT property to ON. Add new sales records that have the desired key values.


正确答案:C
解析:Explanation: DBCC CHECKIDENT is used to check the current identity value for the specified table. It can be set to correct the identity value by specifying the RESEED option with DBCC CHECKIDENT.

Note: Example:
Assume that we have a table called test with an identity column with seed (1,1) and 1000 rows and that we delete row 901 to 950. We could then issue the command
DBCC CHECKIDENT (test, reseed, 900)

And load the 50 missing rows. These rows would get the values 901, 902, …,950 in the identity column.
We should then set the identity value to 1000 again:
DBCC CHECKIDENT (test, reseed, 1000)

So that the next new row will have identity 1001.

Incorrect Answers:
A: Exporting the data from the Sales table and then reloading the data will not correct errors contained in the table as these errors will also be exported as they are part of the data already in the table.
B: Exporting the data from the Sales table and then reloading the data will not correct errors contained in the table as these errors will also be exported as they are part of the data already in the table.

D: The SET IDENTITY_INSERT command allows explicit values to be inserted into the identity column of a table. To reuse the old key values from the rows that was deleted would require manual commands and would be awkward. This is not the best solution.

第4题:

A data file become corrupted in your database due to bad sectors on the disk. Because of corruption, you lost all the important tables in that data file. Which method would you use for recovery?()

  • A、 Flash back all the tables in the data file, one by one.
  • B、 Restore the data file to a new location and perform a media recovery.
  • C、 Flash back the database, there is no need to restore the data file.
  • D、 Restore the data file from the most recent backup and flash the database.

正确答案:B

第5题:

You are using flat files as the data source for one of your data warehousing applications. To optimize the application performance, you plan to move the data from the flat files to clustered tables in an Oracle database.While migrating the data, you want to have minimal impact on the database performance and optimize the dataload operation.  Which method would you use to load data into the Oracle database()

  • A、Use the external table population.
  • B、Use the Oracle Data Pump export and import utility.
  • C、Use the conventional path data load of the SQL*Loader utility.
  • D、Use the INSERT INTO...SELECT command to load the data

正确答案:C

第6题:

You are the administrator of a SQL Server 2000 computer in your company's personnel department. Employee data is stored in a SQL Server 2000 database. A portion of the database schema is shown in the exhibit.

You want to create a text file that lists these data columns in the following format title, FirstName, LastName, WorkPhone, PositionName, DepartmentName.

You want to create the text file as quickly as possible. You do not expect to re-create this file, and you want to avoid creating new database objects if possible.

What should you do?

A.Use the bcp utility to export data from each table to a separate text file. Use format files to select the appropriate columns. Merge the data from each text file into a single text file.

B.Create a view that joins data from all three tables include only the columns you want to appear in the text file. Use the bcp utility to export data from the view.

C.Create a SELECT query that joins the data from the appropriate columns in the three tables. Add an INTO clause to the query to create a local temporary table. Use the bcp utility to export data from the local temporary table to a text file.

D.Create a SELECT query that joins the data from the appropriate columns in the three tables. Add an INTO clause to the query to create a global temporary table. Use the bcp utility to export data from the global temporary table to a text file.


正确答案:D
解析:Explanation:Asthecolumnsthatwewantinthetextfileareondifferenttablesinthedatabase,wewouldhavetocombinethecolumnintoatableorview.Becausewewillnotneedtoreproducethefile,wecanwecancombinethecolumnfromthevarioustablesintoaglobaltemporarytablebyusingtheSELECTINTOstatement.Thenweusethebcputilitytoexportthedatafromtheglobaltemporaryfiletoatextfile.Note:Temporarytablesarenotstoredinthecurrentdatabase;theyarestoredinthetempdbsystem.Therearetwotypesoftemporarytables:localtemporarytables,whicharevisibleonlytotheconnectionthatcreatedthem,andglobaltemporarytables,thatarevisibletoallconnections.Ifglobaltemporarytablesarenotdroppedexplicitlybeforetheconnectionthatcreatedthemdisconnects,theyaredroppedassoonasallothertasksstopreferencingthem.Nonewtaskscanreferenceaglobaltemporarytableaftertheconnectionthatcreateditdisconnects.ThebcputilitycopiesdatabetweenaninstanceofSQLServer2000andadatafileinauser-specifiedformat.ItcanbeusedtotransferdatafromaSQLServertabletoadatafileforuseinotherprograms.Furthermore,datacanalsobetransferredoutbyspecifyingaSELECTstatement.Thebcputilitycanuseglobaltemporarytables,butnotlocaltemporarytables.IncorrectAnswers:A:CreatingaglobaltemporarytablebyusingtheSELECTstatementandusingthebcputilitytoexportdatafromthattablewouldrequirelessadministrativeeffortthanusingbcptoexporttherequiredcolumnsfromeachtableintoaseparatetextfileandthenmergingthosetextfilesintoasingletextfile.B:Becausewewouldnotneedtore-createthedatafileagain,itwouldbeeasiertousetheSELECTstatementtocreateaglobaltemporarytableasthesetablesaredroppedautomaticallywhennothingreferencethem.C:Thebcputilitycannotuselocaltemporarytables.Note:Temporarytablesarenotstoredinthecurrentdatabase;theyarestoredinthetempdbsystem.Therearetwotypesoftemporarytables:localtemporarytables,whicharevisibleonlytotheconnectionthatcreatedthem,andglobaltemporarytables,thatarevisibletoallconnections.

第7题:

You are planning to import customer data from the Customer table and the Country table in your SQL Server 2000 database into a SQL Server 2005 database. You want to ensure that during the import process,each value in the CountryCode column of the Customer table has a corresponding record in the CountryCode column in the Country table of the SQL Server 2005 database. You define a foreign key between these two tables. Thus,referential integrity will guarantee that the import routine fails if there are any records where a CountryCode value does not exist in the Country table but does exist in the Customer table. You need to ensure that the import process does not fail if records are encountered that do not exist in the Country table. What should you do?()

  • A、Drop the foreign key. Import the data by using the script. Re-create the foreign key.
  • B、Create a CHECK constraint.
  • C、Create a DML INSTEAD OF trigger that writes the failed records to a file or table.
  • D、Create a DML AFTER trigger that writes the failed records to a file or table.

正确答案:C

第8题:

You are the administrator of a SQL Server 2000 database. You import a table of geographic information from a Microsoft access database into a SQL Server 2000 database. The table has 12,000 rows. Each row averages 5,000 bytes. The table contains lockup data that does not change.

You want to minimize the size of the data file and the time required to back up the data. Which two actions should you take? (Each correct answer presents part of the solution. Choose two)

A. Create a 60-MB data file named geography.ndf

B. Create a 95-MB data file named geography.ndf

C. Create a 60-MB data file named geography.mdf

D. Create a 95-MB data file named geography.mdf

E. Place the table in the PRIMARY filegroup.

F. Place the table in a new filegroup named LOCATION.


正确答案:BF
B,F 解析:Explanation: As SQL Server 2000 supports backing up or restoring individual files or file groups within a database, it is possible to reduce back up time by creating a separate data file table so that only that table will be backed up. This separate data file will have to be a secondary data file because a database can only have one primary data file, which is identified by the .mdf extension, it is the starting point of the database and locates all the other files in the database. Secondary data files are identified by the .ndf extension and comprise all of the data files except the primary data file. A database need not have a secondary data file and it is also possible to create multiple secondary data files on database.

Rows are stored in data pages. Rows cannot cross different data pages. The size of data page in SQL Server 2000 (or SQL 7.0) is 8,192 bytes. We can only store one row in every data page in this scenario. Thus, to estimate the size of the tale we would need to multiply the number of rows, 12,000 in this scenario, by 8,192 bytes. This will give us a table size of 98,304,000 bytes. As computer data storage is calculated using the binary rather than the decimal system, there is 1,024 bytes per Kb and 1,024 Kb per MB, rather than 1,000 bytes per Kb and 1,000 Kb per MB, we thus require a database size of at least 93.75 MB.

Incorrect Answers:
A: The data size of this table is insufficient as a minimum size of 93.75 MB is required.

C: The data size of this table is insufficient as a minimum size of 93.75 MB is required. Furthermore, the .mdf file extension indicate in this solution implies that the data file will be placed in the primary filegroup. It would thus not be possible to backup the data file pertaining to the table only.

D: The .mdf file extension indicate in this solution implies that the data file will be placed in the primary filegroup. It would thus not be possible to backup the data file pertaining to the table only.

E: As SQL Server 2000 supports backing up or restoring individual files or file groups within a database, it is possible to reduce back up time by creating a separate data file table so that only that table will be backed up. This separate data file will have to be a secondary data file because a database can only have one primary data file, which is identified by the .mdf extension, it is the starting point of the database and locates all the other files in the database.

第9题:

Your database is in NOARCHIVELOG mode. After which two operations you should take the backup of control file?()

  • A、adding a new user to the database
  • B、dropping a user from the database
  • C、dropping a table from the database
  • D、dropping a data file from a tablespace
  • E、adding a new tablespace to the database

正确答案:D,E

第10题:

Which two statements are true regarding the usage of the SQL*Loader utility()

  • A、You can load data into multiple tables during the same load session.
  • B、You can load data from multiple files to a table during the same load session.
  • C、You cannot perform selective data loading based on the values available in the records.
  • D、You can use an export file generated by the EXPDP utility as an input data file to load the data.
  • E、You can load data only if the input file is available on the disk and tape but not in a named pipes.

正确答案:A,B

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