Company Database ERD

Connected Environment or Active Connection

Imports System.DataImports System.Data.SqlClient

Public Class Form1 Dim con As SqlConnection Dim comm As SqlCommand Dim rd As SqlDataReader

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load con = New SqlConnection con.ConnectionString = "data source=Majeed;initial catalog=company;user id=sa;Password=11326" comm = New SqlCommand comm.Connection = con 'For Fill Deptartment Combo comm = New SqlCommand("Select * from Dept") comm.CommandType = CommandType.Text comm.Connection = con If comm.Connection.State = ConnectionState.Closed Then comm.Connection.Open() End If rd = comm.ExecuteReader cbodeptname.Items.Clear() While rd.Read cbodeptname.Items.Add(rd("deptno") & "-" & rd("DeptName")) End While rd.Close() comm.Dispose() End Sub

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Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click EmptyForm() ‘Procedure Look at Db01 End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim qry As String Dim cnt As Integer qry = "insert into emp values (" & _ TextBox1.Text & "," & _ "'" & TextBox2.Text & "'," & _ TextBox3.Text & "," & _ TextBox4.Text & ")" comm.CommandText = qry comm.Connection.Open() cnt = comm.ExecuteNonQuery() comm.Connection.Close() MessageBox.Show(cnt & " record affected") EmptyForm() End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click Dim qry As String qry = "select * from emp" & _ " where empno=" & TextBox1.Text comm.CommandText = qry comm.Connection.Open() rd = comm.ExecuteReader 'Initially the record pointer is at top within the reader object If rd.HasRows Then rd.Read() 'Move to the next record TextBox2.Text = rd("ename") TextBox3.Text = rd("sal") TextBox4.Text = rd("deptno") Else MessageBox.Show("Record not found") EmptyForm() End If comm.Connection.Close() End Sub

Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click Dim qry As String Dim cnt As Integer qry = "update emp set " & _ "ename='" & TextBox2.Text & "'," & _ "sal=" & TextBox3.Text & "," & _ "deptno=" & TextBox4.Text & _ " where empno=" & TextBox1.Text comm.CommandText = qry comm.Connection.Open() cnt = comm.ExecuteNonQuery() comm.Connection.Close() MessageBox.Show(cnt & " record affected") EmptyForm() End Sub

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Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click Dim qry As String Dim cnt As Integer qry = "delete from emp" & _ " where empno=" & TextBox1.Text comm.CommandText = qry comm.Connection.Open() cnt = comm.ExecuteNonQuery() comm.Connection.Close() MessageBox.Show(cnt & " record affected") EmptyForm() End SubEnd Class

Disconnected Environment or Deactive Connection

Db01

Imports System.DataImports System.Data.SqlClient

Public Class Form1 Dim con As SqlConnection Dim adapt As SqlDataAdapter Dim adaptBld As SqlCommandBuilder Dim ds As DataSet Dim drFound As DataRow = Nothing

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load '1 con = New SqlConnection con.ConnectionString = "data source=Majeed;initial catalog=company;user id=sa;password=11326" '2 adapt = New SqlDataAdapter("select * from emp", con) '3 adaptBld = New SqlCommandBuilder(adapt) '4 ds = New DataSet() '5 adapt.Fill(ds, "empTable") End Sub

Private Sub EmptyForm()

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TextBox1.Text = "" TextBox2.Text = "" TextBox3.Text = "" TextBox4.Text = "" TextBox1.Focus() End Sub Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click EmptyForm() End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim dr As DataRow dr = ds.Tables("empTable").NewRow() dr("empno") = Convert.ToInt32(TextBox1.Text) dr("ename") = TextBox2.Text dr("sal") = Convert.ToSingle(TextBox3.Text) dr("deptno") = Convert.ToInt32(TextBox4.Text) ds.Tables("empTable").Rows.Add(dr) MessageBox.Show("Record Inserted in Memory") EmptyForm() End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click Dim eno As Integer = Convert.ToInt32(TextBox1.Text) Dim x As Integer For x = 0 To ds.Tables("empTable").Rows.Count - 1 If Convert.ToInt32(ds.Tables("empTable").Rows(x)("empno")) = eno Then drFound = ds.Tables("empTable").Rows(x) Exit For End If Next If drFound IsNot Nothing Then TextBox2.Text = drFound("ename").ToString() TextBox3.Text = drFound("sal").ToString() TextBox4.Text = drFound("deptno").ToString() End If End Sub

Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click If drFound IsNot Nothing Then drFound("ename") = TextBox2.Text drFound("sal") = Convert.ToSingle(TextBox3.Text) drFound("deptno") = Convert.ToInt32(TextBox4.Text) MessageBox.Show("Record Updated in Memory") End If EmptyForm() drFound = Nothing End Sub

Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click If drFound IsNot Nothing Then drFound.Delete() MessageBox.Show("Record Deleted from memory") End If EmptyForm() drFound = Nothing End Sub

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Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click adapt.Update(ds, "empTable") MessageBox.Show("Changes Saved in Database") End SubEnd Class

Db02 ‘Form Layout same as Db01Imports System.DataImports System.Data.SqlClientPublic Class Form1 Dim con As SqlConnection Dim adapt As SqlDataAdapter Dim adaptBld As SqlCommandBuilder Dim deptAdapt As SqlDataAdapter Dim ds As DataSet Dim drFound As DataRow = Nothing

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load con = New SqlConnection con.ConnectionString = "data source=Majeed;initial catalog=company;user id=sa;password=11326" adapt = New SqlDataAdapter("select * from emp", con) adaptBld = New SqlCommandBuilder(adapt) deptAdapt = New SqlDataAdapter("select * from dept", con) ds = New DataSet() adapt.Fill(ds, "empTable") deptAdapt.Fill(ds, "deptTable") 'Adding constraints ds.Tables("deptTable").Constraints.Add("deptPk", New DataColumn() {ds.Tables("deptTable").Columns("deptno")}, True) ds.Tables("empTable").Constraints.Add("empPk", New DataColumn() {ds.Tables("empTable").Columns("empno")}, True) ds.Tables("empTable").Constraints.Add("empFk", New DataColumn() {ds.Tables("deptTable").Columns("deptno")}, New DataColumn() {ds.Tables("empTable").Columns("deptno")}) End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click EmptyForm() ‘Procedure Look at Db01 End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim dr As DataRow dr = ds.Tables("empTable").NewRow() dr("empno") = Convert.ToInt32(TextBox1.Text) dr("ename") = TextBox2.Text dr("sal") = Convert.ToSingle(TextBox3.Text) dr("dno") = Convert.ToInt32(TextBox4.Text) Try ds.Tables("empTable").Rows.Add(dr) MessageBox.Show("Record Inserted in Memory") EmptyForm() Catch exp As ConstraintException MessageBox.Show("PK: " & exp.Message) Catch exp As InvalidConstraintException MessageBox.Show("FK: " & exp.Message) End Try End Sub

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Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click Dim eno As Integer = Convert.ToInt32(TextBox1.Text) drFound = ds.Tables("empTable").Rows.Find(New Object() {eno}) If drFound IsNot Nothing Then TextBox2.Text = drFound("ename").ToString() TextBox3.Text = drFound("sal").ToString() TextBox4.Text = drFound("deptno").ToString() Else MessageBox.Show("Record not Found") End If End Sub

Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click If drFound IsNot Nothing Then Try drFound("ename") = TextBox2.Text drFound("sal") = Convert.ToSingle(TextBox3.Text) drFound("deptno") = Convert.ToInt32(TextBox4.Text) MessageBox.Show("Record Updated in Memory") EmptyForm() Catch exp As InvalidConstraintException MessageBox.Show("FK: " & exp.Message) End Try End If drFound = Nothing End Sub

Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click If drFound IsNot Nothing Then drFound.Delete() MessageBox.Show("Record Deleted from memory") End If EmptyForm() drFound = Nothing End Sub

Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click adapt.Update(ds, "empTable") MessageBox.Show("Changes Saved in Database") End SubEnd Class

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Db03 ‘Form Layout same as Db01

Imports System.DataImports System.Data.SqlClientPublic Class Form1 Dim con As SqlConnection Dim adapt As SqlDataAdapter Dim adaptBld As SqlCommandBuilder Dim deptAdapt As SqlDataAdapter Dim ds As CompanyDataSet Dim drFound As CompanyDataSet.empRow = Nothing

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load con = New SqlConnection con.ConnectionString = "data source=Majeed;initial catalog=company;user id=sa;password=11326" adapt = New SqlDataAdapter("select * from emp", con) adaptBld = New SqlCommandBuilder(adapt) deptAdapt = New SqlDataAdapter("select * from dept", con) ds = New CompanyDataSet deptAdapt.Fill(ds, "dept") adapt.Fill(ds, "emp") End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click EmptyForm() ‘Procedure Look at Db01 End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim dr As CompanyDataSet.empRow dr = ds.emp.NewempRow dr.empno = Convert.ToInt32(TextBox1.Text) dr.ename = TextBox2.Text dr.sal = Convert.ToSingle(TextBox3.Text) dr.deptno = Convert.ToInt32(TextBox4.Text) Try ds.emp.Rows.Add(dr) MessageBox.Show("Record Inserted in Memory") EmptyForm() Catch exp As ConstraintException MessageBox.Show("PK: " & exp.Message) Catch exp As InvalidConstraintException MessageBox.Show("FK: " & exp.Message) End Try End Sub

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Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click Dim eno As Integer = Convert.ToInt32(TextBox1.Text) drFound = ds.emp.FindByempno(eno) If drFound IsNot Nothing Then TextBox2.Text = drFound.ename TextBox3.Text = drFound.sal.ToString() TextBox4.Text = drFound.deptno.ToString() Else MessageBox.Show("Record not Found") End If End Sub

Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click If drFound IsNot Nothing Then Try drFound.ename = TextBox2.Text drFound.sal = Convert.ToSingle(TextBox3.Text) drFound.deptno = Convert.ToInt32(TextBox4.Text) MessageBox.Show("Record Updated in Memory") EmptyForm() Catch exp As InvalidConstraintException MessageBox.Show("FK: " & exp.Message) End Try End If drFound = Nothing End Sub

Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click If drFound IsNot Nothing Then drFound.Delete() MessageBox.Show("Record Deleted from memory") End If EmptyForm() drFound = Nothing End Sub

Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click adapt.Update(ds, "emp") MessageBox.Show("Changes Saved in Database") End SubEnd Class

Db04

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Imports System.DataImports System.Data.SqlClientPublic Class Form2 Dim con As SqlConnection Dim empAdapt As SqlDataAdapter Dim bldAdapt As SqlCommandBuilder Dim empSource As BindingSource Dim companyDs As DataSet1 Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load con = New SqlConnection con.ConnectionString = "data source=Majeed;initial catalog=company;user id=sa;password=11326" empAdapt = New SqlDataAdapter("select * from emp", con) bldAdapt = New SqlCommandBuilder(empAdapt) companyDs = New DataSet1() empAdapt.Fill(companyDs, "emp") 'A empSource = New BindingSource() empSource.DataSource = companyDs empSource.DataMember = "emp" 'B empNavigator.BindingSource = empSource 'C TextBox1.DataBindings.Add(New Binding("Text", empSource, "empno")) TextBox2.DataBindings.Add(New Binding("Text", empSource, "ename")) TextBox3.DataBindings.Add(New Binding("Text", empSource, "sal")) TextBox4.DataBindings.Add(New Binding("Text", empSource, "deptno")) End Sub

Private Sub SaveToolStripButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveToolStripButton.Click Try empAdapt.Update(companyDs, "emp") Catch exp As Exception MessageBox.Show(exp.Message) End Try MessageBox.Show("Changes Saved") End SubEnd Class

Connection String With Microsoft Access

Imports System.Data.OleDbPublic Class Form1 Dim con As OleDbConnection Dim comm As OleDbCommand Dim rd As OleDbDataReader Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load con = New OleDbConnection con.ConnectionString = "provider=microsoft.jet.oledb.4.0;data source=" & _ Application.StartupPath & "\company.mdb" End SubEnd Class

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