1. Visual Basic
Database Programming

2. Topic & Structure of the lesson
Introduction
Database Concepts
Active X ADODB
Add Records
Update
Delete Records

3. Learning Outcomes At the end of this lecture, you should be able to :
Create a database table
Use Active X Data Objects (ADODB)
Write Structured Query Language (SQL)
Add Records
Update Records

4. Key Words used in this lecture
If you have mastered this topic, you should be able to use
the following terms correctly in your assignments and
exams:
ADODB
Add New
Update
Open
Close
EOF

5. Creating a Database Table
Start Microsoft Access
Create a table
Enter the field names
Ensure that you have a primary key field
Save the table as tblstudent

6. Active X Data Objects (ADODB)
Newest Database Connectivity method in VB6.0.
Supports Hierarchical Flexi Grid Control.
Easier to program and debug.
Allows Connection String method to connect to a database.

7. Steps to Connect To A Database
Select Project References
Select Microsoft ActiveX Data Objects 2.1 Library
Write the connection string to connect to a database

8. Database Connection Dim cn as adodb.connection Private Sub Form_Load()
Dim connstring As String
Set cn = New ADODB.Connection
connstring = “Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=c:\newadodb\devin.mdb"
cn.Open connstring
End Sub

9. Group Exercise
Write a procedure to connect to a database called library.mdb

10. Adding A New Record
Execute the recordset’s AddNew method. This adds a new, blank record to the end of the recordset.
Assign values to the new record.
Write the record to the database using the recordset’s Update method.

11. Adding A New Record Private Sub cmdadd_Click()
dim rs as adodb.recordset
set rs = new adodb.recordset
Dim strsql As String
strsql = "select * from login where firstname = null"
rs.Open strsql, cn, adOpenKeyset, adLockOptimistic
rs.AddNew
rs.Fields("id") = Val(Txtid.text)
rs.Fields("firstname") = txtfirstname.text
rs.Fields("lastname") = txtlastname.text
rs.Fields("age") = Val(txtage.text)
rs.Update
rs.Close
End Sub

12. Quick Review Question
Write a procedure to accept Student-ID, student name, address, phone-number from text boxes.
Write the record to a student-table.

13. Basic SQL Statements SELECT * from TableName WHERE criteria
(*) indicates all fields from a Table
Select * From Student Where name = ‘John’
Select StudentID, Name from tblstudent
Select * from Student where name = ‘”& txtname.text & “’”
Select * from tblstudent order by name – To Sort by Name

14. Quick Review Question
Write a SQL statement to select all fields from tblpassenger.
Write a SQL statement to select passengerID, name, address and phone from tblpassenger.
Write a SQL statement to select all fields from tblpassenger where name = Smith
Write a SQL statement to select all fields from tblpassenger where name is from a textbox input.

15. Updating a Record Used to update a record or group of records
Search the specific records using an SQL statement.
If the record is found then update the record using Update method.
Use an EOF Statement to check if a record exist
If the record is not found display an Error Message.
Close the recordset once update is complete

16. Updating a Record Private Sub cmdupdate_Click()
Dim rs as adodb.recordset ‘declare recordset
Set rs = new adodb.recordset ‘set the recordset
Dim strsql As String
strsql = “select * from login where ID = “ & txtid.text & “”
rs.Open strsql, cn, adOpenKeyset, adLockOptimistic
If rs.eof then ‘Record Does Not Exist
Msgbox “Record Not Found”
Else
rs.Fields("age") = Val(txtage.text)
rs.Update
End if
rs.close
End Sub

17. Quick Review Question
Write a procedure to search for a Student ID and update the student’s address and phone number.
If the studentID is not found display an error message using a Msgbox.
Use tblstudent as the table name.

18. Deleting a Record To delete a record or group of records.
Search for a record to be deleted.
Use .EOF to check if record is found.
Use .delete command to delete the record.

19. Deleting a Record Private Sub Command2_Click() Dim strsql As String
Dim rs as adodb.recordset
Set rs = new adodb.recordset
strsql = “select * from login where firstname = ‘ ” & txtfirstname.text & “ ’ ”
rs.Open strsql, cn, adOpenKeyset, adLockOptimistic
If rs.EOF Then
MsgBox "Record Not Found"
Else
rs.Delete
End If
rs.Close
End Sub

20. Quick Review Question
Write a program to request for a Student-ID and delete it from the student-table.
If the Student-ID is not found display an error message using a MsgBox.

21. Question and Answer Session
Q & A

22. Next Session
Displaying and Searching Records

23. Displaying and Searching Records

24. Learning Outcomes At the end of this lecture you should be able to:
Display records to a list box
Select records from a lit box
Search records using the like operator
Display records to a combo box

25. Key Words List Box Do Until Like
If you have mastered this topic, you should be able to use the following
terms correctly in your assignments and exams:
List Box
Do Until
Like

26. References Database Access with Visual Basic 6 Jeffrey P Mc Manus
SAMS Publication
Visual Basic 6 How to Program
Deitel and Deitel
Chapter 18

27. Display Records to a List Box
Private Sub Command4_Click()
Dim rs As ADODB.Recordset
Set rs = New ADODB.Recordset
Dim sql As String
sql = "Select * from login"
rs.Open sql, cn, adOpenKeyset, adLockOptimistic
List1.Clear

28. Display Data to a List Box
Do Until rs.EOF
List1.AddItem rs.Fields("firstname")
List1.ItemData(List1.NewIndex) = rs.Fields("ID")
rs.MoveNext
Loop
End Sub

29. Group Exercise
Write a procedure to display all students name from tblstudent to a listbox.

30. Search Using List Box Click Event
Private Sub list1_click()
Dim rs as adodb.recordset
Dim strsql As String
Set rs = new adodb.recordset
sql = "select * from login where ID = " & _
List1.ItemData(List1.ListIndex)
rs.Open sql, cn, adOpenKeyset, adLockOptimistic
Text3.text = rs.Fields("firstname")
Text4.text = rs.Fields("lastname")
rs.Close
End Sub

31. Search Using Like Operator
Private Sub Command1_Click()
Dim rs As ADODB.Recordset
Dim sql as string
Set rs = New ADODB.Recordset
Sql = "Select * from login where firstname Like “ & _
“ ’ ” & Trim(Text1.text) & “%’ ”
rs.Open sql, cn , adOpenStatic, adLockOptimistic, adCmdText
List1.Clear
Do Until rs.EOF
List1.AddItem rs.Fields("firstname") & " " & rs.Fields("lastname")
rs.MoveNext
Loop
rs.Close
End Sub

32. Group Exercise
Write a procedure to search for student’s name beginning with the letter “A”.
Accept the student’s name using a text box
Display the above records to a list box

33. Display records to a Combo Box
Private sub form_load()
sql = "select * from login"
rs.Open sql, cn, adOpenKeyset,adLockOptimistic
Do Until rs.EOF
Combo1.AddItem rs.Fields("firstname")
rs.MoveNext
Loop
rs.Close
End sub

34. Combo Click Private Sub Combo1_click() Dim sql As String
sql = "Select * from login where firstname = '" & Combo1.text & "'"
rs.Open sql, cn, adOpenKeyset, adLockOptimistic
Text8.text = rs.Fields("ID")
Text1.text = rs.Fields("firstname")
Text2.text = rs.Fields("lastname")
Text5.text = rs.Fields("age")
rs.Close

35. Form Unload
Private sub Form_Unload(Cancel as Integer)
cn.close
set cn = nothing
End Sub

36. Data Grids and Multiple Table Handling

37. Learning Outcomes At the end of this lecture you should be able to :
Display records to a Microsoft Hierarchical Flexi Grid (MSHFGrid)
Display selected records to a Microsoft Hierarchical Flexi Grid
Selecting a Record on a MSHFGrid
Multiple Table Handling

38. Key Words
MSHFGrid
Text Matrix
EOF

39. References Database Access with Visual Basic 6 Jeffrey P Mc Manus
SAMS Publication
Visual Basic 6 Programming
T Say
Prentice Hall
Visual Basic 6 How to Program
Deitel and Deitel
Chapter 18

40. MS HF Grid
HF Grid looks like a spreadsheet with rows and columns
MSHFGrid is used to display records in a presentable format
MSHF Grid can be used to select an item

41. Procedure 1. MSHF Grid must be loaded from project / components
2. Select Project /Components and Click Microsoft Hierarchical Flexi Grid Control 6.0
Click Grid on Tool Bar and draw the Grid on the Form
Write Code to display records on the grid

42. Displaying Records on HF Grid
grid1.Visible = False Hide the grid
Dim str As String
Dim rs As ADODB.Recordset
Set rs = New ADODB.Recordset
str = “select * from login where firstname like ‘ “ & Trim(Text1.text) & “%’ ”
rs.Open str, cn, adOpenKeySet, adLockOptimistic
If rs.BOF Then
MsgBox “Record Not Found”
Exit Sub
End If

43. Displaying Records on HF Grid
grid1.Refresh
Set grid1.DataSource = rs
With grid1
.TextMatrix(0, 1) = "ID"
.TextMatrix(0, 2) = "Firstname"
.TextMatrix(0, 3) = "Lastname"
.TextMatrix(0, 4) = "DOB"
.TextMatrix(0, 5) = "AGE"
End With
grid1.Visible = True - Show the Grid
rs.close

44. Group Exercise
Write a program to search for a student-ID from tblstudent and display the students particulars to a Data Grid.
If the student ID is not found display an error message.

45. Display Selected Fields on HF Grid
Private Sub Command2_Click()
Dim rstitles as adodb.recordset
Set rstitles = new adodb.recordset
Dim sql ,text As String
Dim row As Integer
sql = “Select * from login where firstname like ‘” &
Text1.text & “%’ ”
rstitles.Open sql, cn, adOpenKeyset, adLockOptimistic
grdtitles.Rows = 1
If rstitles.EOF Then
rstitles.Close
Exit Sub
End If

46. Display Selected Fields on HF Grid
Do Until rstitles.EOF
row = row + 1
text = row & vbTab & rstitles.Fields("firstname") & vbTab & rstitles.Fields("lastname")
grdtitles.AddItem text
rstitles.MoveNext
Loop
rstitles.Close
End Sub

47. Group Exercise
Write a procedure to total up all the marks for each student in the student-table and display the average on a text box.
Use student as the table name
Use rs.recordcount to get the number of records in a table.

48. Selecting a Record on a Grid
Private Sub grid1_Click()
a = grid1.TextMatrix(grid1.row, grid1.Col)
Msgbox a
End Sub

49. Multiple Table Handling
Extract data from two or more tables
Used to display data to a report for printing
SID
S-name
Age
Phone
Related
Book ID
SID
Book Title

50. Multiple Table Handling
Format :
Select table1.fieldname,table2.fieldname from table1,table2
Example :
Select student.name, student.id, library.title,library.bookid from student, library where student.sid = library.sid

51. Multiple Table Handling
sql = “select login.firstname, login.lastname ,profile.title, profile.author, profile.isbn from login , profile where profile.loginid = login.id and login.id = “& txtid.text &””
rs.Open sql, cn, adOpenKeyset, adLockOptimistic
grid1.Refresh
Set grid1.DataSource = rs
With grid1
.TextMatrix(0, 1) = "Firstname"
.TextMatrix(0, 2) = "Lastname"
.TextMatrix(0, 3) = "Book Title"
.TextMatrix(0, 4) = "Author"
.TextMatrix(0, 5) = "ISBN"
End With
rs.Close

52. Group Exercise D-ID D-Name D-Floor D-Phone Emp-ID D-ID Emp-Name
Department -Table
Emp-ID
D-ID
Emp-Name
Employee -Table
Write an SQL statement to access the following fields : DID, D-Name, D-Floor, Emp-ID , E-Name where a particular D-ID exists in the Employee Table

53. Group Exercise
Write a procedure that will accept a user name and a password from two text boxes. If the user name and password is found in the database display “Valid User” otherwise display “Invalid User”. Use a MsgBox to display the appropriate message.

54. Search Records Between Two Dates
Private Sub Command8_Click()
Dim rs As ADODB.Recordset
Dim sql As String
Set rs = New ADODB.Recordset
sql = "Select * FROM profile WHERE borrowdate between #" & Format(CDate(mskstart.text), "mm/dd/yyyy") & "#AND#" & Format(CDate(mskend.text), "mm/dd/yyyy") & "#"
rs.Open sql, cn, adOpenKeyset, adLockOptimistic
List1.Clear
If rs.EOF Then
MsgBox "RECORDS IN THAT DATE RANGE ARE NOT FOUND", vbExclamation
Exit Sub
End If

55. Search Records Between Two Dates
grid1.Visible = True
grid1.Rows = 1
Do Until rs.EOF
row = row + 1
text = row & vbTab & rs.Fields("Title") & vbTab & rs.Fields("author") & vbTab & rs.Fields("isbn")
grid1.AddItem text
rs.MoveNext
Loop
grid1.FixedRows = 1 ‘To Write data on the First Row
End Sub

56. Move Next – SQL statement
Place a select statement in the form load to select all records.
Select statement should not be placed in the move next and move previous procedure.
Private sub Form_load()
Dim rs1 as adodb.Recordset
Set rs1 = new adodb.Recordset
sql = “select * from login”
rs1.Open sql, cn, adOpenKeySet, adLockOptimistic
End sub

57. Move Next Private Sub Command5_Click() rs1.MoveNext
If rs1.EOF = True Then
rs1.MoveFirst
End If
Text8.text = rs1.Fields("ID")
Text1.text = rs1.Fields("firstname")
Text2.text = rs1.Fields("lastname")
Text5.text = rs1.Fields("age")
End Sub

58. Group Exercise
Write a procedure to move to a previous record
You need to use the following key words
BOF
IF….ELSE…THEN
MovePrevious

59. Move Previous To move to a previous record rs1.MovePrevious
If rs1.BOF = True Then
rs1.MoveLast
End If
Text8.text = rs1.Fields("ID")
Text1.text = rs1.Fields("firstname")
Text2.text = rs1.Fields("lastname")
Text5.text = rs1.Fields("age")

60. Group Exercise Write a program to accept a students ID ,name,
age, intake and dob.
Save the record to a tblstudent
Write a procedure to delete a studentID
Write a procedure to move to a next record
Write a procedure to move to a previous record

61. VISUAL BASIC
DATA REPORTS
Bound and Unbound

62. Learning Outcomes At the end of this lecture you should be able to :
Write a Bound Data Report to display all records for hard copy printing
Write an Unbound Data Report to display selected records for hard copy printing

63. Key Words
Data Report
Bound
Unbound
Data Environment

64. Bound Data Report
Is used to display records on screen for hardcopy printing
Resembles like an MS-Word Document
Primarily used to display all records for printing

65. Data Report
Records Displayed Here

66. Bound Data Report - Step 1
Select Project Click Components

67. Bound Data Report – Step 2
Click Project and Click Data Environment
Right Click Connection1 - Select Properties
Select Microsoft Jet OLE DB Provider
Click Next
Select Database Path and Database Name
Click Test Connection
Right Click Connection1 – Add Command1
Right Click Command1 – Select Properties
Select Table from Database Object
Select Table Name

68. Bound Data Report – Step 3
Click on Command1 Tree View
You will be able to see the field name
Select Project – Add Data Report
Drag field to the Detail Section of the Data Report
Select Data Report Properties
Place Command1 in Data Member
Place Data Environment1 in Data Source
Run Data Report
In Form 1 - Private Sub Command1_Click ()
DataReport1.Show
End Sub

69. Bound Data Report - Rules
If database name is not selected and test connection is clicked an error message is displayed.
If the previous steps are not followed the program will not run.

70. Unbound Data Report

71. Unbound Data Report
Unbound data report is used to display selected fields to a data report
Query statements can be written to select certain records from a table
Does not depend on the Data Environment
Users must write program code to display records on a data report

72. Unbound Data Report - Step 1

73. Unbound Data Report - Step 2
Insert Text Box to Detail Section1 as a field
Insert Labels to Page Header - Section2
Write Code to display records to the data report

74. Group Exercise Write a program to accept a students ID ,name, age,
intake and dob.
Save the record to a tblstudent
Write a procedure to delete a studentID
Write a procedure to move to a next record
Write a procedure to move to a previous record

75. Homework
Write a program that will search a particular students name from <student-table> and display the Name, ID , Age on an un bound data report.
The table has the following fields :
Name ID
Age

76. Homework
Write a program to display all records from a table to a data report
Write a program to search for a users IC Number and display his/her name, address, postcode, age , gender, tel-no to a bound data report