A unique index
A composite index
A check constraint
A generated column
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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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.
You need to design the storage of the loan response message. Which actions or actions should you perform?（）A、Use the xml data type to store the message.B、Use a user-defined data type to store the message.C、Use the nvarchar（max） data type to store the message.D、Use a check constraint to validate that the correct tags are used.E、Use an XML schema definition （XSD） to validate that the correct tags are used.F、Use a foreign key constraint to validate that the correct tags are used.
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 supports the XML data type?（）A、A unique indexB、A composite indexC、A check constraintD、A generated column
An index called ORD_CUSTNAME_IX has been created on the CUSTNAME column in the ORDERS table using the following command： SQL>CREATE INDEX ord_custname_ix ON orders（custname）； The ORDERS table is frequently queried using the CUSTNAME column in the WHERE clause. You want to check the impact on the performance of the queries if the index is not available. You do not want the index to be dropped or rebuilt to perform this test. Which is the most efficient method of performing this task？（）A、 disabling the indexB、 making the index invisibleC、 making the index unusableD、 using the MONITORING USAGE clause for the index
Which three statements are true regarding the data types in Oracle Database 10g/11g?（）A、Only one LONG column can be used per table B、A TIMESTAMP data type column stores only time values with fractional seconds C、The BLOB data type column is used to store binary data in an operating system file D、The minimum column width that can be specified for a VARCHAR2 data type column is one E、The value for a CHAR data type column is blank-padded to the maximum defined column width
