1Z0-007
多选题In which three cases would you use the USING clause?（）AYou want to create a nonequijoin.BThe tables to be joined have multiple NULL columns.CThe tables to be joined have columns of the same name and different data types.DThe tables to be joined have co
题目
You want to create a nonequijoin.
The tables to be joined have multiple NULL columns.
The tables to be joined have columns of the same name and different data types.
The tables to be joined have columns with the same name and compatible data types.
You want to use a NATURAL join, but you want to restrict the number of columns in the join condition.
相似问题和答案
第1题：
A.A table referenced in the FROM clause has no indexed column.
B.The table referenced in the FROM clause has more than 200 columns.
C.Two or more tables in the FROM clause have identical column names.
D.The FROM clause contains two or more tables in the SELECT statement.
第2题：
Which two statements are true regarding the USING clause in table joins?（）
- A、It can be used to join a maximum of three tables
- B、It can be used to restrict the number of columns used in a NATURAL join
- C、It can be used to access data from tables through equijoins as well as nonequijoins
- D、It can be used to join tables that have columns with the same name and compatible data types
正确答案:B,D
第3题：
A. The underlying tables must have data.
B. You need SELECT privileges on the view.
C. The underlying tables must be in the same schema.
D. You need SELECT privileges only on the underlying tables.
第4题：
In which case would you use a FULL OUTER JOIN?（）
- A、Both tables have NULL values.
- B、You want all unmatched data from one table.
- C、You want all matched data from both tables.
- D、You want all unmatched data from both tables.
- E、One of the tables has more data than the other.
- F、You want all matched and unmatched data from only one table.
正确答案:D
第5题：
Which three statements are true regarding subqueries?（）
- A、Subqueries can contain GROUP BY and ORDER BY clauses
- B、Main query and subquery can get data from different tables
- C、Main query and subquery must get data from the same tables
- D、Subqueries can contain ORDER BY but not the GROUP BY clause
- E、Only one column or expression can be compared between the main query and subquery
- F、 Multiple columns or expressions can be compared between the main query and subquery
正确答案:A,B,E
第6题：
A.You want to create a nonequijoin.
B.The tables to be joined have multiple NULL columns.
C.The tables to be joined have columns of the same name and different data types.
D.The tables to be joined have columns with the same name and compatible data types.
E.You want to use a NATURAL join, but you want to restrict the number of columns in the join condition.
第7题：
In which of the following situations should correlation names be used?（）
- A、A table referenced in the FROM clause has no indexed column.
- B、The table referenced in the FROM clause has more than 200 columns.
- C、Two or more tables in the FROM clause have identical column names.
- D、The FROM clause contains two or more tables in the SELECT statement.
正确答案:C
第8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.
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9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10题：
Which three statements about subqueries are true? （）
- A、A main query can have more than one subquery.
- B、A subquery can have more than one main query.
- C、The subquery and main query must retrieve data from the same table.
- D、The subquery and main query can retrieve data from different tables.
- E、Only one column or expression can be compared between the subquery and main query.
- F、Multiple columns or expression can be compared between the subquery and main query.
正确答案:A,C,E