Deck 13: Working With Access Databases and Linq

Question 1

If you do not take deliberate steps in your code to handle exceptions, Visual Basic "handles" them for you.

Answer 1

True

Question 2

A(n) ____ is an electronic file that contains an organized collection of related information.

A) field
B) computer database
C) dataset
D) exception

Answer 2

B

Question 3

In most tables, one of the fields uniquely identifies each record and is called the ____.

A) exception
B) foreign key
C) primary key
D) cell

Answer 3

C

Question 4

A ____ is a copy of the data (database fields and records) that can be accessed by an application.

A) position property
B) child table
C) dataset
D) bound control

Question 5

A ____ is a single item of information about a person, place, or thing-such as a name, a salary amount, a Social Security number, or a price.

A) table
B) record
C) dataset
D) field

Question 6

A database file contained in a project is referred to as a logic database file.

Question 7

The field used to link a child table to a parent table is known as the ____ in the child table.

A) record
B) foreign key
C) cell
D) primary key

Question 8

Databases created using Microsoft Access are relational databases.

Question 9

A group of related records is called a ____.

A) table
B) field
C) datagrid
D) primary key

Question 10

Connecting an object to a control is called ____.

A) linking
B) Order By clause
C) LINQ
D) binding

Question 11

A(n) ____ is a group of related fields that contain all of the necessary data about a specific person, place, or thing.

A) object
B) dataset
C) record
D) exception

Question 12

The computer can retrieve data stored in a relational format both quickly and easily, but the data must be displayed in a specific order.

Question 13

When you drag an object from a dataset to an empty area on the form, the computer creates a control and automatically binds the object to it.

Question 14

Each column in a table represents a record and each row represents a field.

Question 15

The controls connected to an object in a dataset are known as ____.

A) bound controls
B) navigator controls
C) tables
D) fields

Question 16

A(n) ____ stores information in tables composed of columns and rows, similar to the format used in a spreadsheet.

A) relational database
B) object
C) bound control
D) dataset

Question 17

A relational database can contain one or more tables.

Question 18

Before an application can access the data stored in a database, you need to connect the application to the database.

Question 19

A BindingNavigator control displays table data in a row and column format, similar to a spreadsheet.

Question 20

When you drag an object from the Data Sources window to an existing control, the computer does not create a new control; rather, it merely binds the object to the existing control.

Question 21

The ____ object provides the connection between the DataSet and the bound controls on the form.

A) TableAdapter
B) DataGridView
C) BindingSource
D) BindingNavigator

Question 22

Which of the following statements selects all of the records in the tblStudents table?

A) Dim records = Select student In tblStudents
B) Dim records = Select student From StudentsDataSet.tblStudents
C) Dim records = From student In StudentsDataSet.tblStudents
Select student
D) Dim records = Select student In StudentsDataSet.tblStudents
From student

Question 23

A label, text box, or button can be added to the BindingNavigator control by accessing the control's task box and clicking ____.

A) AddNewItem
B) Properties
C) Insert Standard Items
D) Edit Items

Question 24

The BindingSource object's ____ methods move the record pointer to the first, last, next, or previous record in the dataset.

A) Position
B) View
C) Move
D) Navigation

Question 25

Case-Based Critical Thinking Questions Case 1 - MaidToOrder
The database for a cleaning service company contains the following table, named tblCustomer, that includes customer invoice data. The InvoiceNum, CustomerNum, and InvoicePaid fields contain text. The InvoiceDate field contains dates. The InvoiceAmt field contains numbers.
To create a DataGridView control on the form, you would click on the ____ object in the Data Sources window and drag it to the form.

A) CustomerNum
B) InvoiceNum
C) CustomerDataSet
D) tblCustomer

Question 26

If a user is not allowed to add a record, you should deselect the ____ check box within the task list for the DataGridView control.

A) Enable Adding
B) Enable Deleting
C) Edit Items
D) BindingNavigatorAddNewItem

Question 27

The tblItems table contains a numeric field named Price. Which of the following statements finds the lowest price for an item and assigns the result to the dblLowPrice variable?

A) Dim dblLowPrice As Double = Min item In Items.DataSet.tblItems
Select item.Price
B) Dim dblLowPrice As Double = Aggregate item In Items.DataSet.tblItems
Select item.Price Into Min()
C) Dim dblLowPrice As Double = Select Min item In Items.DataSet.tblItems
D) Dim dblLowPrice As Double = Select Aggregate item In Items.DataSet.tblItems
Into Min()

Question 28

The way Visual Basic saves changes to a local database file is determined by the file's ____ property.

A) BindingNavigator
B) Position
C) BindingSource
D) Copy to Output Directory

Question 29

The ____ statement is used for exception handling in a procedure.

A) Try...Catch
B) LINQ
C) Order By
D) aggregate

Question 30

An error that occurs while an application is running is called a(n) ____.

A) logic error
B) runtime error
C) exception
D) message

Question 31

The ____ object can be used to save to the database any changes made to the data contained in the DataSet.

A) TableAdapter
B) TblEmployBindingSource
C) BindingSource
D) DataGridView

Question 32

You can create a query in Visual Basic 2015 using a language feature called ____.

A) ASP
B) SQL
C) Java
D) Language-Integrated Query

Question 33

The ____ property (of the DataGridView) allows you to format a column's data, as well as change the column's width and alignment.

A) AutoSizeColumnsMode
B) DefaultCellStyle
C) BindingNavigator
D) DataGridView

Question 34

The ____ object is responsible for retrieving the appropriate information from the database and storing it in the DataSet.

A) TableAdapter
B) TblEmployBindingSource
C) BindingSource
D) DataGridView

Question 35

You can use a(n) ____ to specify both the records to select in a dataset and the order in which to arrange the records.

A) condition
B) parameter
C) query
D) aggregate operator

Question 36

The ____ clause of LINQ is used to arrange the records in either ascending (the default) or descending order by one or more fields.

A) Order By
B) condition
C) query
D) Where

Question 37

Case-Based Critical Thinking Questions Case 1 - MaidToOrder
The database for a cleaning service company contains the following table, named tblCustomer, that includes customer invoice data. The InvoiceNum, CustomerNum, and InvoicePaid fields contain text. The InvoiceDate field contains dates. The InvoiceAmt field contains numbers.
You are responsible for connecting the Access database that contains the tblCustomer table to an application. You must first use the Data Source Configuration Wizard to ____.

A) test to see if the database is connected to the application
B) add a new data source
C) preview the contents of the dataset
D) bind the controls to the dataset

Question 38

The BindingSource object stores the position of the record pointer in its ____ property.

A) View
B) Position
C) Navigation
D) Cell

Question 39

When an application is running, you can use the ____ control to move from one record to the next in the dataset, as well as to add or delete a record and save any changes made to the dataset.

A) DataSet
B) BindingNavigator
C) TableAdapter
D) BindingSource

Question 40

The intersection of a row and a column in a DataGridView control is called a ____.

A) cell
B) table
C) record
D) key

Question 41

What are the advantages to storing data in a relational database?

Question 42

Writing LINQ Statements
The tblBicycle table contains five fields: ItemNum, ItemName, Color, Price, and Quantity. The Price and Quantity fields are numeric; all other fields are text. The dataset name is BicycleDataSet.
Write a LINQ statement to select all records.

Question 43

Writing LINQ Statements
The tblBicycle table contains five fields: ItemNum, ItemName, Color, Price, and Quantity. The Price and Quantity fields are numeric; all other fields are text. The dataset name is BicycleDataSet.
Write the statement needed to assign the contents of the records variable to the BindingSource object for the tblBicycle table. Explain why this should be done in an application.

Question 44

Writing LINQ Statements
The tblBicycle table contains five fields: ItemNum, ItemName, Color, Price, and Quantity. The Price and Quantity fields are numeric; all other fields are text. The dataset name is BicycleDataSet.
Write the code to calculate the average price of all of the bicycles in inventory.

Question 45

Write the code needed to include a Try...Catch statement that will handle an error that might occur while saving in an application. Use the following statements in the Try block, along with a message for the user of the Student Data Application that notifies the user the changes have been saved. Provide an error message if an exception occurs.
Me.Validate()
Me.TblStudentBindingSource.EndEdit()
Me.TableAdapterManager.UpdateAll(Me.StudentsDataSet)

Question 46

Case-Based Critical Thinking Questions Case 1 - MaidToOrder
The database for a cleaning service company contains the following table, named tblCustomer, that includes customer invoice data. The InvoiceNum, CustomerNum, and InvoicePaid fields contain text. The InvoiceDate field contains dates. The InvoiceAmt field contains numbers.
You need to make sure the user of the application can add records but cannot delete any records. Which of the following needs to be performed?

A) Remove the Add new button from the TblCustomerBindingNavigator control.
B) Remove the Delete button from the TblCustomerBindingNavigator control.
C) Remove the Save button from the TblCustomerBindingNavigator control.
D) b and c

Question 47

Write the statements to move the record pointer to the first and last records in the dataset for the Customer table.

Question 48

Writing LINQ Statements
The tblBicycle table contains five fields: ItemNum, ItemName, Color, Price, and Quantity. The Price and Quantity fields are numeric; all other fields are text. The dataset name is BicycleDataSet.
Write a LINQ statement to select the records in descending order by the Quantity field.

Question 49

What is the DataGridView control and how is it used?

Question 50

Write the statements to move the record pointer to the previous and next records in the dataset for the Vehicle table.

Question 51

Problems - Correcting Logic and Code Errors
The following sample of code contains errors. Rewrite the incorrect statements to correct all errors.
Private Sub TblItemsBindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TblItemsBindingNavigatorSaveItem.Click
Try
Validate()
Me.TblItemsBindingSource
Me.TableAdapterManager.UpdateAll(Me.ItemsDataSet)
MessageBox.Show("Changes saved", "Books Galore",
MessageBoxButtons.OK,
MessageBoxIcon.Information)
Catch ex
MessageBox.Show(ex.Message, "Books Galore",
MessageBoxButtons.OK,
MessageBoxIcon.Information)
End
End Sub

Question 52

Relational databases contain multiple tables that relate to each other in some way. How are primary and foreign keys used in such a database?

Question 53

Case-Based Critical Thinking Questions Case 1 - MaidToOrder
The database for a cleaning service company contains the following table, named tblCustomer, that includes customer invoice data. The InvoiceNum, CustomerNum, and InvoicePaid fields contain text. The InvoiceDate field contains dates. The InvoiceAmt field contains numbers.
Which of the following statements will select all invoices of $200.00 or more and arrange the invoices in ascending order by Customer number?

A) Dim records = From customer In CustomerDataSet.tblCustomer
Where customer.InvoiceAmt > 200
Order By invoice.CustomerNum
Select customer
B) Dim records = From customer In CustomerDataSet.tblCustomer
Where customer.InvoiceAmt > 200
Order invoice.CustomerNum Ascending
Select customer
C) Dim records = From CustomerDataSet.tblCustomer
Where customer.InvoiceAmt > 200
Order invoice.CustomerNum
Select customer
D) Dim records = From customer In CustomerDataSet.tblCustomer
Where customer.InvoiceAmt
Order By invoice.CustomerNum
Select customer

Question 54

Writing LINQ Statements
The tblBicycle table contains five fields: ItemNum, ItemName, Color, Price, and Quantity. The Price and Quantity fields are numeric; all other fields are text. The dataset name is BicycleDataSet.
Write a LINQ statement to select all bicycles with a price greater than $450. Arrange the bicycles in descending order by price.

Question 55

List the five objects that are placed in the component tray when a table object is bound to a DataGridView control.

Question 56

Case-Based Critical Thinking Questions Case 1 - MaidToOrder
The database for a cleaning service company contains the following table, named tblCustomer, that includes customer invoice data. The InvoiceNum, CustomerNum, and InvoicePaid fields contain text. The InvoiceDate field contains dates. The InvoiceAmt field contains numbers.
Which of the following statements will calculate a total for all of the unpaid invoices?

A) Dim decTotalUnpaid = Aggregate customer In CustomerDataSet.tblCustomer
Select customer.InvoicePaid Into Sum()
B) Dim decTotalUnpaid = Aggregate customer In CustomerDataSet.tblCustomer
Select customer.InvoiceAmt Into Sum()
C) Dim decTotalUnpaid = Aggregate customer In CustomerDataSet.tblCustomer
Where customer.InvoicePaid.ToUpper = "N"
Select customer.InvoiceAmt Into Average()
D) Dim decTotalUnpaid = Aggregate customer In CustomerDataSet.tblCustomer
Where customer.InvoicePaid.ToUpper = "N"
Select customer.InvoiceAmt Into Sum()

Question 57

Define the terms "record," "field," and "table." Provide examples of each term when you are defining them.

Question 58

Writing LINQ Statements
The tblBicycle table contains five fields: ItemNum, ItemName, Color, Price, and Quantity. The Price and Quantity fields are numeric; all other fields are text. The dataset name is BicycleDataSet.
Write a LINQ statement to calculate the total value of the inventory.

Question 59

Private Sub btnNext_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnNext.Click
' moves to the next record
TblClientBindingSource.MovePrevious()
End Sub
Private Sub btnPrevious_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnPrevious.Click
' moves to the previous record
TblClientBindingSource.MoveNext()
End Sub
Private Sub btnDisplay_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnDisplay.Click
' displays all clients or
' specific clients for a certain state
Const strPROMPT As String = "Enter one or more " &
"letters. Leave blank to retrieve all records."
Dim strSearch As String
' get user input
strSearch = InputBox(strPROMPT, "Find State").ToUpper
' select the appropriate records
Dim records = ClientDataSet.tblClient
For client.State.ToUpper Like strSearch & "*"
Select
' display the records
TblClientBindingSource.DataSource = records
End Sub

Question 60

Writing LINQ Statements
The tblBicycle table contains five fields: ItemNum, ItemName, Color, Price, and Quantity. The Price and Quantity fields are numeric; all other fields are text. The dataset name is BicycleDataSet.
Write a LINQ statement to select all blue bicycles. Order the bicycles in ascending order by quantity.