What is
ADO.NET Dataset
The ADO.NET DataSet
contains DataTableCollection and their DataRelationCollection . It represents a
collection of data retrieved from the Data Source. We can use Dataset in
combination with DataAdapter
class. The DataSet object offers a disconnected data source architecture. The
Dataset can work with the data it contain, without knowing the source of the
data coming from. That is , the Dataset can work with a disconnected mode from
its Data Source . It gives a better advantage over DataReader ,
because the DataReader is working only with the connection oriented Data
Sources
The DataAdapter object allows us
to populate DataTables in a DataSet. We can use Fill method of the DataAdapter
for populating data in a Dataset. The DataSet can be filled either from a data
source or dynamically. A DataSet can be saved to an XML file and then loaded
back into memory very easily. The following links shows more information of
Dataset in details.
How to
Dataset with Sql Server
The DataSet contains the copy of
the data we requested through the SQL statement. We can use Dataset in
combination with SqlDataAdapter class . The SqlDataAdapter object allows us to
populate Data Tables in a DataSet. We can use Fill
method in the SqlDataAdapter for populating data in a Dataset.VB.NET Source Code
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As SqlConnection
Dim command As SqlCommand
Dim adapter As New SqlDataAdapter
Dim ds As New DataSet
Dim i As Integer
Dim sql As String
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
connection = New SqlConnection(connetionString)
Try
connection.Open()
command = New SqlCommand(sql, connection)
adapter.SelectCommand = command
adapter.Fill(ds)
adapter.Dispose()
command.Dispose()
connection.Close()
For i = 0 To ds.Tables(0).Rows.Count - 1
MsgBox(ds.Tables(0).Rows(i).Item(0) & " -- " & ds.Tables(0).Rows(i).Item(1))
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Data Source=ServerName;Initial Catalog=DatabaseName;User
ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
How to
Dataset with OLEDB Data Source
The DataSet contains the copy of
the data we requested through the SQL statement. We can use Dataset in
combination with OleDbDataAdapter class . The OleDbDataAdapter object allows us
to populate Data Tables in a DataSet. We can use Fill
method in the OleDbDataAdapter for populating data in a Dataset.VB.NET Source Code
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As OleDbConnection
Dim oledbAdapter As OleDbDataAdapter
Dim ds As New DataSet
Dim sql As String
Dim i As Integer
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
connection = New OleDbConnection(connetionString)
Try
connection.Open()
oledbAdapter = New OleDbDataAdapter(sql, connection)
oledbAdapter.Fill(ds)
oledbAdapter.Dispose()
connection.Close()
For i = 0 To ds.Tables(0).Rows.Count - 1
MsgBox(ds.Tables(0).Rows(i).Item(0) & " -- " & ds.Tables(0).Rows(i).Item(1))
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
Search
Tables in a Dataset Sql Server
The DataSet contains DataTableCollection
and their DataRelationCollection. The DataTableCollection contains zero or more
DataTable objects. The Dataset may comprise
data for one or more members, corresponding to the number of rows. The
SqlDataAdapter object allows us to populate DataTables in a DataSet.In some situations we have to find how many tables inside the Dataset Object contains . The following VB.NET source code shows how to find the tables inside the Dataset.
VB.NET Source Code
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As SqlConnection
Dim command As SqlCommand
Dim adapter As New SqlDataAdapter
Dim ds As New DataSet
Dim tables As DataTable
Dim i As Integer
Dim sql As String
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
connection = New SqlConnection(connetionString)
Try
connection.Open()
command = New SqlCommand(sql, connection)
adapter.SelectCommand = command
adapter.Fill(ds, "SQL Temp Table")
adapter.Dispose()
command.Dispose()
connection.Close()
For Each tables In ds.Tables
MsgBox(tables.TableName)
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Data Source=ServerName;Initial Catalog=DatabaseName;User
ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
Search
Tables in a Dataset OLEDB Data Source
The DataSet contains
DataTableCollection and their DataRelationCollection. The DataTableCollection
contains zero or more DataTable objects. The data inside Table is
in the form of Rows and Columns . The OleDbDataAdapter object allows us to
populate DataTables in a DataSet.In some situations we have to find how many tables inside the Dataset Object contains . The following VB.NET source code shows how to find the tables inside the Dataset.
VB.NET Source Code
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As OleDbConnection
Dim oledbAdapter As OleDbDataAdapter
Dim ds As New DataSet
Dim sql As String
Dim i As Integer
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
connection = New OleDbConnection(connetionString)
Try
connection.Open()
oledbAdapter = New OleDbDataAdapter(sql, connection)
oledbAdapter.Fill(ds, "OLEDB Temp Table")
oledbAdapter.Dispose()
connection.Close()
For i = 0 To ds.Tables.Count - 1
MsgBox(ds.Tables(i).TableName)
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables
Dataset
table row count in SQL Server
The DataSet contains copy of the
data we requested through the SQL statement. The DataSet consists of
DataTableCollection and their DataRelationCollection. The DataTableCollection
contains zero or more DataTable objects. The data set may comprise data for one
or more members, corresponding to the number of rows. The following VB.NET
source code shows how to find the number of rows in a table that resides in the
Dataset.VB.NET Source Code
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As SqlConnection
Dim command As SqlCommand
Dim adapter As New SqlDataAdapter
Dim ds As New DataSet
Dim sql As String
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
connection = New SqlConnection(connetionString)
Try
connection.Open()
command = New SqlCommand(sql, connection)
adapter.SelectCommand = command
adapter.Fill(ds, "SQL Temp Table")
adapter.Dispose()
command.Dispose()
connection.Close()
MsgBox("Number of row(s) - " & ds.Tables(0).Rows.Count)
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Data Source=ServerName;Initial Catalog=DatabaseName;User
ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
Dataset
table row count - OLEDB Data Source
The DataSet contains copy of the
data we requested through the SQL statement. The DataSet consists of
DataTableCollection and their DataRelationCollection. The DataTableCollection
contains zero or more DataTable objects. The data inside Table is in the form
of Rows and Columns . The following VB.NET source code shows how to find the
number of rows in a table that resides in the Dataset from OLEDB Data Source.VB.NET Source Code
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As OleDbConnection
Dim oledbAdapter As OleDbDataAdapter
Dim ds As New DataSet
Dim sql As String
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
connection = New OleDbConnection(connetionString)
Try
connection.Open()
oledbAdapter = New OleDbDataAdapter(sql, connection)
oledbAdapter.Fill(ds, "OLEDB Temp Table")
oledbAdapter.Dispose()
connection.Close()
MsgBox("number of Row(s) - " & ds.Tables(0).Rows.Count)
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
How to find
column definition - Sql Server
Dataset represents a collection
of data retrieved from the Data Source. The Dataset can work with the data it
contains, without knowing the source of the data coming from. The
SqlDataAdapter object allows us to populate DataTable in a DataSet. We can use Fill
method in the SqlDataAdapter for populating data in a Dataset. The Dataset can
contains more than one Table at a time. The data inside Table is in the form of
Rows and Columns .In some situations we have to find the column headers in a DataTable. There is a ColumnsCollection object in the Datatable hold the column Definitions.
VB.NET Source Code
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As SqlConnection
Dim command As SqlCommand
Dim adapter As New SqlDataAdapter
Dim ds As New DataSet
Dim dt As DataTable
Dim column As DataColumn
Dim sql As String
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
connection = New SqlConnection(connetionString)
Try
connection.Open()
command = New SqlCommand(sql, connection)
adapter.SelectCommand = command
adapter.Fill(ds, "SQL Temp Table")
adapter.Dispose()
command.Dispose()
connection.Close()
dt = ds.Tables(0)
For Each column In dt.Columns
MsgBox(column.ColumnName)
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Data Source=ServerName;Initial Catalog=DatabaseName;User
ID=UserName;Password=Password"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
How to find
column definition - OLEDB Data Source
Dataset represents a collection of
data retrieved from the Data Source.. The OleDbDataAdapter object allows us to
populate DataTable in a DataSet. We can use Fill
method in the OleDbDataAdapter for populating data in a Dataset. The Dataset can contain more than one Table at
a time. The data set may comprise data for one or more members, corresponding
to the number of rows.In some situations we have to find the column headers in a DataTable. There is a ColumnsCollection object in the Datatable hold the column Definitions.
VB.NET Source Code
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As OleDbConnection
Dim oledbAdapter As OleDbDataAdapter
Dim ds As New DataSet
Dim dt As DataTable
Dim sql As String
Dim i As Integer
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
connection = New OleDbConnection(connetionString)
Try
connection.Open()
oledbAdapter = New OleDbDataAdapter(sql, connection)
oledbAdapter.Fill(ds, "OLEDB Temp Table")
oledbAdapter.Dispose()
connection.Close()
dt = ds.Tables(0)
For i = 0 To dt.Columns.Count - 1
MsgBox(dt.Columns(i).ColumnName)
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString
= "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
sql = "Your SQL Statement Here"
You have to replace the string with your real time variables.
How to
create DataSet without Databse
VB.NET Source Code
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim ds As New DataSet
Dim dt As DataTable
Dim dr As DataRow
Dim idCoulumn As DataColumn
Dim nameCoulumn As DataColumn
Dim i As Integer
dt = New DataTable()
idCoulumn = New DataColumn("ID", Type.GetType("System.Int32"))
nameCoulumn = New DataColumn("Name", Type.GetType("System.String"))
dt.Columns.Add(idCoulumn)
dt.Columns.Add(nameCoulumn)
dr = dt.NewRow()
dr("ID") = 1
dr("Name") = "Name1"
dt.Rows.Add(dr)
dr = dt.NewRow()
dr("ID") = 2
dr("Name") = "Name2"
dt.Rows.Add(dr)
ds.Tables.Add(dt)
For i = 0 To ds.Tables(0).Rows.Count - 1
MsgBox(ds.Tables(0).Rows(i).Item(0) & " -- " & ds.Tables(0).Rows(i).Item(1))
Next i
End Sub
End Class
How to
multiple tables in Dataset - Sql Server
The DataSet contains
DataTableCollection and their DataRelationCollection. The DataTableCollection
contains zero or more DataTable objects. The SqlDataAdapter
object allows us to populate DataTables in a DataSet. We can use Fill method in
the SqlDataAdapter for populating data in a Dataset.We can populate Dataset with more than one table at a time using SqlDataAdapter Object . The following VB.NET source code shows how to a single SqlDataAdapter fill Dataset with multiple tables.
VB.NET Source Code
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As SqlConnection
Dim command As SqlCommand
Dim adapter As New SqlDataAdapter
Dim ds As New DataSet
Dim i As Integer
Dim firstSql As String
Dim secondSql As String
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
connection = New SqlConnection(connetionString)
Try
connection.Open()
command = New SqlCommand(firstSql, connection)
adapter.SelectCommand = command
adapter.Fill(ds, "First Table")
adapter.SelectCommand.CommandText = secondSql
adapter.Fill(ds, "Second Table")
adapter.Dispose()
command.Dispose()
connection.Close()
'retrieve first table data
For i = 0 To ds.Tables(0).Rows.Count - 1
MsgBox(ds.Tables(0).Rows(i).Item(0) & " -- " & ds.Tables(0).Rows(i).Item(1))
Next
'retrieve second table data
For i = 0 To ds.Tables(1).Rows.Count - 1
MsgBox(ds.Tables(1).Rows(i).Item(0) & " -- " & ds.Tables(1).Rows(i).Item(1))
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString =
"Data Source=ServerName;Initial Catalog=DatabaseName;User
ID=UserName;Password=Password" sql = "Your SQL Statement Here"
How to multiple tables in Dataset - OLEDB Data Source
The DataSet contains DataTableCollection and their DataRelationCollection. The DataTableCollection contains zero or more DataTable objects. The OleDbDataAdapter object allows us to populate DataTables in a DataSet. We can use Fill method in the OleDbDataAdapter for populating data in a Dataset. We can populate Dataset with more than one table at a time using OleDbDataAdapter Object . The following VB.NET source code shows how to a single OleDbDataAdapter fill Dataset with multiple tables.
VB.NET Source Code
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As OleDbConnection
Dim oledbAdapter As OleDbDataAdapter
Dim ds As New DataSet
Dim firstSql As String
Dim secondSql As String
Dim i As Integer
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
connection = New OleDbConnection(connetionString)
Try
connection.Open()
oledbAdapter = New OleDbDataAdapter(firstSql, connection)
oledbAdapter.Fill(ds, "First Table")
oledbAdapter.SelectCommand.CommandText = secondSql
oledbAdapter.Fill(ds, "Second Table")
oledbAdapter.Dispose()
connection.Close()
'retrieve first table data
For i = 0 To ds.Tables(0).Rows.Count - 1
MsgBox(ds.Tables(0).Rows(i).Item(0) & " -- " & ds.Tables(0).Rows(i).Item(1))
Next
'retrieve second table data
For i = 0 To ds.Tables(1).Rows.Count - 1
MsgBox(ds.Tables(1).Rows(i).Item(0) & " -- " & ds.Tables(1).Rows(i).Item(1))
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString =
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;" firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
You have to replace the string with your real time variables.
How to add
relations between tables in a Dataset
The DataSet contains
DataTableCollection and their DataRelationCollection. The DataSet.Relations
property is an instance of the DataRelationsCollection Object. We can create
parent child data relations between DataTable using Datarelation Object. We can
relate one or more column from different tables using DataRelation Object . The
columns involved in the DataRelation should be identical data types. That is the parent and child
column should be similar Data Types.VB.NET Source Code
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As SqlConnection
Dim command As SqlCommand
Dim adapter As New SqlDataAdapter
Dim ds As New DataSet
Dim firstSql As String
Dim secondSql As String
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
connection = New SqlConnection(connetionString)
Try
connection.Open()
command = New SqlCommand(firstSql, connection)
adapter.SelectCommand = command
adapter.Fill(ds, "Table1")
adapter.SelectCommand.CommandText = secondSql
adapter.Fill(ds, "Table2")
adapter.Dispose()
command.Dispose()
connection.Close()
'creating data relations
Dim relation As DataRelation
Dim table1Column As DataColumn
Dim table2Column As DataColumn
'retrieve column
table1Column = ds.Tables("Table1").Columns(0)
table2Column = ds.Tables("table2").Columns(0)
'relating tables
relation = New DataRelation("relation", table1Column, table2Column)
'assign relation to dataset
ds.Relations.Add(relation)
MsgBox("Data relation completed")
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString =
"Data Source=ServerName;Initial Catalog=DatabaseName;User
ID=UserName;Password=Password" firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
You have to replace the string with your real time variables.
How to
merge tables in a Dataset - Sql Server
The DataSet contains copy of the
data we requested through the SQL statement. The SqlDataAdapter object allows us
to populate DataTable in a DataSet. We can use Fill
method in the SqlDataAdapter for populating data in a Dataset. We can populate Dataset with more
than one table at a time using SqlDataAdapter Object. The DataTableCollection
contains zero or more DataTable objects.In some situation we want to combine the result of multiple SQL query as a single result set. In that case we can use the Dataset's Merge method for doing this. The tables involved in the merge should be identical, that is the columns are similar data types .
VB.NET Source Code
Imports System.Data.SqlClient
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As SqlConnection
Dim command As SqlCommand
Dim adapter As New SqlDataAdapter
Dim ds As New DataSet
Dim dt As DataTable
Dim firstSql As String
Dim secondSql As String
Dim i As Integer
connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password"
firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
connection = New SqlConnection(connetionString)
Try
connection.Open()
command = New SqlCommand(firstSql, connection)
adapter.SelectCommand = command
adapter.Fill(ds, "Table(0)")
adapter.SelectCommand.CommandText = secondSql
adapter.Fill(ds, "Table(1)")
adapter.Dispose()
command.Dispose()
connection.Close()
ds.Tables(0).Merge(ds.Tables(1))
dt = ds.Tables(0)
For i = 0 To dt.Rows.Count - 1
MsgBox(dt.Rows(i).Item(0) & " -- " & dt.Rows(i).Item(1))
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString = "Data Source=ServerName;Initial
Catalog=DatabaseName;User ID=UserName;Password=Password"
firstSql = "Your
First SQL Statement Here"
secondSql = "Your
Second SQL Statement Here"
You have to replace the string with your real time variables.
How to merge tables in a Dataset - OLEDB Data
Source
The DataSet contains copy of the
data we requested through the SQL statement. The OleDbDataAdapter object allows
us to populate DataTable in a DataSet. We can use Fill method
in the OleDbDataAdapter for populating data in a Dataset. We can populate
Dataset with more than one table at a time using OleDbDataAdapter Object. The
DataTableCollection contains zero or more DataTable objects. In some situation
we want to combine the result of multiple SQL query results as a single result
set. In that case we can use the Dataset's Merge method for doing this. The
tables involved in the merge should be identical. The following VB.NET source
code shows how to merge the tables from two different dataset.VB.NET Source Code
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim connection As OleDbConnection
Dim oledbAdapter As OleDbDataAdapter
Dim ds1 As New DataSet
Dim ds2 As New DataSet
Dim dt As DataTable
Dim firstSql As String
Dim secondSql As String
Dim i As Integer
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
connection = New OleDbConnection(connetionString)
Try
connection.Open()
oledbAdapter = New OleDbDataAdapter(firstSql, connection)
oledbAdapter.Fill(ds1, "First Table")
oledbAdapter.SelectCommand.CommandText = secondSql
oledbAdapter.Fill(ds2, "Second Table")
oledbAdapter.Dispose()
connection.Close()
ds1.Tables(0).Merge(ds2.Tables(0))
dt = ds1.Tables(0)
For i = 0 To dt.Rows.Count - 1
MsgBox(dt.Rows(i).Item(0) & " -- " & dt.Rows(i).Item(1))
Next
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class
connetionString =
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;" firstSql = "Your First SQL Statement Here"
secondSql = "Your Second SQL Statement Here"
You have to replace the string with your real time variables.
ให้นักศึกษาสร้าง From Login ตามต้องการโดยตกแต่งให้สวยงาม จากนั้นให้ทำการเขียน Code เพื่อทำการเชื่อมต่อฐานข้อมูลโดยวันนี้จะใช้ Microsoft Access 2003 และ MS SQL Server 2005
· สิ่งที่นักศึกษาจะได้ทำการเรียนรู้
1. การ Import แบบ
Imports System.Data.OleDb
Imports System.Data.SqlClient
2. การประกาศตัวแปรเพื่อทำการรับค่าต่างๆ
3. การเขียนโปรแกรมแบบการใช้ Function เพื่อเรียกใช้
4. และการกำหนด Properties ต่างๆให้กับเครื่องมือที่ใช้
Code ดีมากครับอาจารย์
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ตอบลบcode VB.net ครับ
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