You added a PHONE_NUMBER column of NUMBER data type to an existing EMPLOYEES table. The EMPLOYEES table already contains records of 100 employees. Now, you want to enter the phone numbers of each of the 100 employees into the table. Some of the employees may not have a phone number available. Which data manipulation operation do you perform?()
第1题:
Click the Exhibit button and examine the data in the EMPLOYEES table.On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID column is a NOT NULL column.Evaluate this DELETE statement:DELETE employee_id, salary, job_idFROM employeesWHERE dept_id = 90;Why does the DELETE statement fail when you execute it?()
A.There is no row with dept_id 90 in the EMPLOYEES table.
B.You cannot delete the JOB_ID column because it is a NOT NULL column.
C.You cannot specify column names in the DELETE clause of the DELETE statement.
D.You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.
第2题:
You create a data block based on a relation table containing a REF column. You select the REF column for your form module. Which statement about the REF column is true?()
第3题:
You added a PHONE_NUMBER column of NUMBER data type to an existing EMPLOYEES table. The EMPLOYEES table already contains records of 100 employees. Now, you want to enter the phone numbers of each of the 100 employees into the table. Some of the employees may not have a phone number available. Which data manipulation operation do you perform? ()
A. MERGE
B. INSERT
C. UPDATE
D. ADD
E. ENTER
F. You cannot enter the phone numbers for the existing employee records.
第4题:
You are creating a form that will access an Oracle8 database. On which three sources can you base a data block?()
第5题:
Which two statements about sequences are true? ()
第6题:
Which two are true about aggregate functions?()
第7题:
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?()
第8题:
Examine the data in the EMPLOYEES table.On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID column is a NOT NULL column.Evaluate this DELETE statement:Why does the DELETE statement fail when you execute it?()
A. There is no row with dept_id 90 in the EMPLOYEES table.
B. You cannot delete the JOB_ID column because it is a NOT NULL column.
C. You cannot specify column names in the DELETE clause of the DELETE statement.
D. You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.
第9题:
A programmer wants to generate values for a numeric ID column in their EXPENSE table. The ID column values need to be incremented by 1000 for each new expense report added to the EXPENSE table. Which DB2 object can be referenced by an INSERT statement to meet thisrequirement?()
第10题:
You are creating a DataTable. You use the following code segment to create the DataTable. (Line numbers are included for reference only.) 01 Dim dt As New DataTable("Products") 02 dt.Columns.Add(New DataColumn("Price", _ GetType(Decimal))) 03 dt.Columns.Add(New DataColumn("Quantity", _ GetType(Int32))) 04 Dim dc As DataColumn = New DataColumn("Total", _ GetType(Decimal)) 05 dt.Columns.Add(dc) You need to ensure that the Total column is set to the value of the Price column multiplied by the Quantity column when new rows are added or changed. What should you do? ()