You create a table with the PER

题目

You create a table with the PERIOD FOR clause to enable the use of the Temporal Validity feature of Oracle Database 12c. Examine the table definition: Which three statements are true concerning the use of the Valid Time Temporal feature for the EMPLOYEES table?()

  • A、The valid time columns employee_time_start and employee_time_end are automatically created.
  • B、The same statement may filter on both transaction time and valid temporal time by using the AS OF TIMESTAMP and PERIOD FOR clauses.
  • C、The valid time columns are not populated by the Oracle Server automatically.
  • D、The valid time columns are visible by default when the table is described.
  • E、Setting the session valid time using DBMS_FLASHBACK_ARCHIVE.ENABLE_AT_VALID_TIME sets the visibility for data manipulatio
如果没有搜索结果或未解决您的问题,请直接 联系老师 获取答案。
相似问题和答案

第1题:

You need to perform these tasks:1. Create and assign a MANAGER role to Blake and Clark2. Grant CREATE TABLE and CREATE VIEW privileges to Blake and ClarkWhich set of SQL statements achieves the desired results? ()

A. CREATE ROLE manager; GRANT create table, create view TO manager; GRANT manager TO BLACK, CLARK;

B. CREATE ROLE manager; GRANT create table, create voew TO manager; GRANT manager ROLE TO BLACK, CLARK;

C. GRANT manager ROLE TO BLACK, CLARK; GRANT create table, create voew TO BLACK CLARK; ***MISSING***


参考答案:A

第2题:

You are granted the CREATE VIEW privilege. What does this allow you to do? ()

A. Create a table view.

B. Create a view in any schema.

C. Create a view in your schema.

D. Create a sequence view in any schema.

E. Create a view that is accessible by everyone.

F. Create a view only of it is based on tables that you created.


参考答案:C

第3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4题:

You are designing an application for a telecom company and you have been asked to design a database table to facilitate monthly bill generation. The bill would include details of customer calls, listed in chronological order.  Which method would you follow to achieve this objective without increasing the overhead of sorting the rows?()

  • A、create a hash cluster to store the data
  • B、create an index cluster to store the data
  • C、create a partitioned table to store the data
  • D、create a sorted hash cluster to store the data
  • E、create a heap table with rowid to store the data

正确答案:D

第5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6题:

Which describes the default behavior when you create a table? ()

A. The table is accessible to all users.

B. Tables are created in the public schema.

C. Tables are created in your schema.

D. Tables are created in the DBA schema.

E. You must specify the schema when the table is created.


参考答案:C

第7题:

You notice that during peak hours, some firewall enforcers contain a high number of auth table entries. As you investigate the issue, you discover that all users are getting auth table mappings to all firewalls, which is not acceptable.What should you do on the Junos Pulse Access Control Service to resolve this problem?()

A. Delete the default auth table mapping policy

B. Create auth table mapping policies that route users to specific resources

C. Create Resource Access policies that permit access to specific resources

D. Create Source Interface policies that route users to specific resources


参考答案:A

第8题:

Examine the statement: Create synonym emp for hr. employees; What happens when you issue the statement? ()

A. An error is generated.

B. You will have two identical tables in the HR schema with different names.

C. You create a table called employees in the HR schema based on you EMP table.

D. You create an alternative name for the employees table in the HR schema in your own schema.


参考答案:D

第9题:

You are granted the CREATE VIEW privilege. What does this allow you to do?()

  • A、Create a table view.
  • B、Create a view in any schema.
  • C、Create a view in your schema.
  • D、Create a sequence view in any schema.
  • E、Create a view that is accessible by everyone.
  • F、Create a view only of it is based on tables that you created.

正确答案:C

第10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

更多相关问题