Youneedtocreateacolumnthatallowsyoutocreateauniqueconstraint.Whichtwo column definitionsshouldyou choose?() A.nvarchar（100）NULLB.nvarchar（max）NOTNULLC.nvarchar（100）NOTNULLD.nvarchar（100）SPARSENULL
Youneedtocreateacolumnthatallowsyoutocreateauniqueconstraint.Whichtwo column definitionsshouldyou choose?()
A.nvarchar（100）NULL
B.nvarchar（max）NOTNULL
C.nvarchar（100）NOTNULL
D.nvarchar（100）SPARSENULL
相关考题：
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GEM机箱的地址插板从下往上依次作用是（）A、Row，notused，Column，MagazineAddressB、Row，Column，notused，MagazineAddressC、Column，Row，notused，MagazineAddressD、notused，Row，Column，MagazineAddress
A表有15条记录，B表有20条记录，下面的语句返回的结果集中的记录数为（）。SELECT column1，column2 FROM AUNIONSELECT column1，column2 FROM BA、15B、20C、300D、35
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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单选题You are a database administrator for your company. The company uses a SQL Server 2005 database that includes a table named Inventory. The table contains a column named Price. A company policy states that the value in the Price column cannot be decreased by more than 10 percent in any single database operation. Updates to the Price column are made by various means， including by using ad hoc queries. You need to ensure that this company policy is enforced. What should you do？（）ACreate a trigger that rolls back changes to the Price column that violate company policy.BCreate a stored procedure that disallows changes to the Price column that violate company policy.COn the Price column， create a check constraint that requires a specified minimum value.DOn the Price column， create a foreign key constraint to a table that contains valid prices.
单选题You created a report from the human resources department based on all the columns in the EMP table. After viewing the report users requested that the cmp_ID columns peers first in the output. How would you change the position of the column?（）AAfter the query. BEnter the report and change the column's position in the field tab. CAlter the column's position in the object navigator. DEnter the report wizard and change the column's position in the data tab. EAlter the column's position within its group and change the layout.
单选题You created a tabular report for human resources department. After viewing layout users have requested that you change the label of the dept column to something more meaningful. How would you change the label in the live previewer?（）AUse the report wizard to change the column label. BClick and high light the column label and replace it with desired text. CClick the column label and alter its property palette. DClick the dept column and alter its property palette.
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单选题For Vee-form engines, （） is shaped to given two slopping surface on which （） are placed at the correct relative angle to each other.Athe bottom of the column；the cylinder blocksBthe top of the column；the cylinder headsCthe top of the column；the cylinder blocksDthe bottom of the column；the cylinder heads
单选题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？（）ADefine 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.BDefine the new column as NOT NULL with a default value of ’Undefined.’CDefine the new column as NULL. Use application logic to enforce the data constraint.DDefine the new column as NULL with a default value of ’Undefined.’
单选题What kind of people did Tina choose to write about in her first column? APeople who were very well known.BPeople who had interesting ideas.CPeople who lived in luxury.
单选题When defining a referential constraint between the parent table T2 and the dependent table T1, which of the following is true?（）AThe list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.BThe list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.CThe list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.DThe list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.
单选题You create the sales report and run it in the live previewer. After which change would the live previewer require the data? （）ARemoving column from the available list in the report wizard. BRemoving the column from the displayed list in the report wizard. CChanging the display width of a column in the report wizard. DAdding a column to both the available list and displayed list in the report wizard. ERemoving a column in the live previewer.
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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 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
单选题A表有15条记录，B表有20条记录，下面的语句返回的结果集中的记录数为（）。SELECT column1，column2 FROM AUNIONSELECT column1，column2 FROM BA15B20C300D35