Monday, February 20, 2012

Online query to my database

Hi. I have a database established by MS SQL, and I want to make online
queries to my database over the net by a GUI developed in Visual Studio .NET
.
Could someone explain the procedure I must follow to accomplish such an aim.
I mean that database is in the desktop computer in my house and I want to
make query from my friend's desktop computer which is somewhere else. Hence,
I need something that should be performed over the net.
Thanls in advanceHi ,
Please go through the following piece of information which will be useful
in your case.
ADO can use any OLE DB provider to establish a connection. The provider is
specified through the Provider property of the Connection object.
Microsoft SQL Server 2000 applications use SQLOLEDB to connect to an
instance of SQL Server, although existing applications can also use MSDASQL
to maintain backward compatibility.
Using the Execute method of the Connection object is one way to execute an
SQL statement against a SQL Server data source.
The Connection object allows you to:
Configure a connection.
Establish and terminate sessions with data sources.
Identify an OLE DB provider.
Execute a query.
Manage transactions on the open connection.
Choose a cursor library available to the data provider.
There are some differences in connection properties between SQLOLEDB and
MSDASQL. For information about connection properties for MSDASQL, see the
MSDN Library at Microsoft Web site.
If you are writing a connection string for use with SQLOLEDB:
Use the Initial Catalog property to specify the database.
Use the Data Source property to specify the server name.
Use the Integrated Security keyword, set to a value of SSPI, to specify
Windows Authentication (recommended),
or
use the User ID and Password connection properties to specify SQL Server
Authentication.
Security Note When possible, use Windows Authentication. If Windows
Authentication is not available, prompt users to enter their credentials at
run time. Avoid storing credentials in a file. If you must persist
credentials, you should encrypt them with the Win32 crypto API. For more
information, see "The Crypto API Function" in the MSDN Library at this
Microsoft Web site.
If you are writing a connection string for use with MSDASQL:
Use the Database keyword or Initial Catalog property to specify the
database.
Use the Server keyword or Data Source property to specify the server name.
Use the Trusted_Connection keyword, set to a value of yes, to specify
Windows Authentication (recommended),
or
Use the UID keyword or User ID property, and the Pwd keyword or Password
property to specify SQL Server Authentication.
Security Note When possible, use Windows Authentication. If Windows
Authentication is not available, prompt users to enter their credentials at
run time. Avoid storing credentials in a file. If you must persist
credentials, you should encrypt them with the Win32 crypto API. For more
information, see "The Crypto API Function" in the MSDN Library at this
Microsoft Web site.
For more information about a complete list of keywords available for use
with a SQLOLEDB connection string, see Connection Object.
Restrictions on Multiple Connections
SQLOLEDB does not allow multiple connections. Unlike MSDASQL, SQLOLEDB does
not attempt to reconnect when the connection is blocked.
Examples
A. Using SQLOLEDB to connect to an instance of SQL Server: setting
individual properties
The following Microsoft Visual Basic code fragments from the ADO
Introductory Visual Basic Sample show how to use SQLOLEDB to connect to an
instance of SQL Server.
' Initialize variables.
Dim cn As New ADODB.Connection
. . .
Dim ServerName As String, DatabaseName As String
' Put text box values into connection variables.
ServerName = txtServerName.Text
DatabaseName = txtDatabaseName.Text
' Specify the OLE DB provider.
cn.Provider = "sqloledb"
' Set SQLOLEDB connection properties.
cn.Properties("Data Source").Value = ServerName
cn.Properties("Initial Catalog").Value = DatabaseName
' Windows NT authentication.
cn.Properties("Integrated Security").Value = "SSPI"
' Open the database.
cn.Open
B. Using SQLOLEDB to connect to an instance of SQL Server: connection
string method
The following Visual Basic code fragment shows how to use SQLOLEDB to
connect to an instance or SQL Server:
' Initialize variables.
Dim cn As New ADODB.Connection
Dim provStr As String
' Specify the OLE DB provider.
cn.Provider = "sqloledb"
' Specify connection string on Open method.
ProvStr = " Server=MyServer;Database=northwind;Trust
ed_Connection=yes"
cn.Open provStr
C. Using MSDASQL to connect to an instance of SQL Server
To use MSDASQL to connect to an instance of SQL Server, use the following
types of connections.
The first type of connection is based on the ODBC API SQLConnect function.
This type of connection is useful in situations where you do not want to
code specific information about the data source. This may be the case if
the data source could change or if you do not know its particulars.
In the code fragment shown, the ConnectionTimeout method sets the
connection time-out value to 100 seconds. Next, the data source name, and
authentication type are passed as parameters to the Open method of the
Connection object, using an ODBC data source named MyDataSource that points
to the northwind database on an instance of SQL Server.
Dim cn As New ADODB.Connection
cn.ConnectionTimeout = 100
' DSN connection
' cn.Open " DSN=MyDataSource;Trusted_Connection=yes;
"
cn.Close
The second type of connection is based on the ODBC API SQLDriverConnect
function. This type of connection is useful in situations where you want a
driver-specific connection string. To make a connection, use the Open
method of the Connection object and specify the driver, server name,
authentication type, and database. You can also specify any other valid
keywords to include in the connection string. For more information about
the keyword list, see SQLDriverConnect.
Dim cn As New ADODB.Connection
' Connection to SQL Server without using ODBC data source.
cn.Open "Driver={SQL
Server};Server=Server1;Database=northwin
d;Trusted_Connection=yes"
cn.Close
Using the Connection Object
In addition to the Command object, an application can use the Connection
object to issue commands, stored procedures, and user-defined functions to
a database as if they were native methods on the Connection object. To
execute a query without using a Command object, an application can pass a
query string to the Execute method of a Connection object.
However, a Command object is required if you want to save and re-execute
the command text, or use query parameters.
To execute a command on the Connection object
Assign a name to the command using the Name property of the Command object.
Set the ActiveConnection property of the Command object to the connection.
Issue a statement where the command name is used as if it were a method on
the Connection object, followed by any parameters.
Create a Recordset object if any rows are returned.
Set the Recordset properties to customize the resulting Recordset.
Using the Connection Object to Execute Commands
This example shows how to use the Execute method of the Connection object
to execute commands.
Dim cn As New ADODB.Connection
. . .
Dim rs As New ADODB.Recordset
cmd1 = txtQuery.Text
Set rs = cn.Execute(cmd1)
After the Connection and Recordset objects are created, the variable cmd1
is assigned the value of a user-supplied query string (txtQuery.Text) from
a Microsoft Visual Basic form. The recordset is assigned the results of a
query, by calling the Execute method of the Connection object, with the
variable cmd1 used as the query string parameter.
Using the Recordset Object
The Recordset object provides methods for manipulating result sets. It
allows you to add, update, delete, and scroll through rows in the recordset.
A Recordset object can be created using the Execute method of the
Connection or Command object.
Each row in a recordset can also be retrieved and updated using the Fields
collection and the Field object. Updates on the Recordset object can be in
an immediate or batch mode. When a Recordset object is created, a cursor is
opened automatically.
The Recordset object allows you to specify the cursor type and location for
fetching the result set. With the CursorType property, you can specify
whether the cursor is read-only, forward-only, static, keyset-driven, or
dynamic. Cursor type determines if a Recordset object can be scrolled or
updated and affects the visibility of changed rows. By default, the cursor
type is read-only and forward-only.
An application can specify the location of the cursor with the
CursorLocation property. This property allows you to specify whether to use
a client or server cursor. The CursorLocation property setting is important
when you use disconnected recordsets.
The first part of the cmdExecute_Click method in the ADO Introductory
Visual Basic Sample shows an example of creating, opening, passing a
command string variable to, and positioning the cursor in a recordset.
Dim cn As New ADODB.Connection
Dim rs As ADODB.Recordset
. . .
cmd1 = txtQuery.Text
Set rs = New ADODB.Recordset
rs.Open cmd1, cn
rs.MoveFirst
. . .
' Code to loop through result set(s)
Thanks and regards,
Girish Sundaram
This posting is provided "AS IS" with no warranties, and confers no rights.|||thank you for now
I will try
Probably I will turn back to you with some questions
"Girish Sundaram" wrote:

> Hi ,
> Please go through the following piece of information which will be useful
> in your case.
> ADO can use any OLE DB provider to establish a connection. The provider is
> specified through the Provider property of the Connection object.
> Microsoft? SQL Server? 2000 applications use SQLOLEDB to connect to an
> instance of SQL Server, although existing applications can also use MSDASQ
L
> to maintain backward compatibility.
> Using the Execute method of the Connection object is one way to execute an
> SQL statement against a SQL Server data source.
> The Connection object allows you to:
> Configure a connection.
>
> Establish and terminate sessions with data sources.
>
> Identify an OLE DB provider.
>
> Execute a query.
>
> Manage transactions on the open connection.
>
> Choose a cursor library available to the data provider.
> There are some differences in connection properties between SQLOLEDB and
> MSDASQL. For information about connection properties for MSDASQL, see the
> MSDN Library at Microsoft Web site.
> If you are writing a connection string for use with SQLOLEDB:
> Use the Initial Catalog property to specify the database.
>
> Use the Data Source property to specify the server name.
>
> Use the Integrated Security keyword, set to a value of SSPI, to specify
> Windows Authentication (recommended),
> or
> use the User ID and Password connection properties to specify SQL Server
> Authentication.
>
> Security Note When possible, use Windows Authentication. If Windows
> Authentication is not available, prompt users to enter their credentials a
t
> run time. Avoid storing credentials in a file. If you must persist
> credentials, you should encrypt them with the Win32? crypto API. For more
> information, see "The Crypto API Function" in the MSDN? Library at this
> Microsoft Web site.
> If you are writing a connection string for use with MSDASQL:
> Use the Database keyword or Initial Catalog property to specify the
> database.
>
> Use the Server keyword or Data Source property to specify the server name.
>
> Use the Trusted_Connection keyword, set to a value of yes, to specify
> Windows Authentication (recommended),
> or
> Use the UID keyword or User ID property, and the Pwd keyword or Password
> property to specify SQL Server Authentication.
>
> Security Note When possible, use Windows Authentication. If Windows
> Authentication is not available, prompt users to enter their credentials a
t
> run time. Avoid storing credentials in a file. If you must persist
> credentials, you should encrypt them with the Win32 crypto API. For more
> information, see "The Crypto API Function" in the MSDN Library at this
> Microsoft Web site.
> For more information about a complete list of keywords available for use
> with a SQLOLEDB connection string, see Connection Object.
> Restrictions on Multiple Connections
> SQLOLEDB does not allow multiple connections. Unlike MSDASQL, SQLOLEDB doe
s
> not attempt to reconnect when the connection is blocked.
> Examples
> A. Using SQLOLEDB to connect to an instance of SQL Server: setting
> individual properties
> The following Microsoft Visual Basic? code fragments from the ADO
> Introductory Visual Basic Sample show how to use SQLOLEDB to connect to an
> instance of SQL Server.
> ' Initialize variables.
> Dim cn As New ADODB.Connection
> . . .
> Dim ServerName As String, DatabaseName As String
> ' Put text box values into connection variables.
> ServerName = txtServerName.Text
> DatabaseName = txtDatabaseName.Text
> ' Specify the OLE DB provider.
> cn.Provider = "sqloledb"
> ' Set SQLOLEDB connection properties.
> cn.Properties("Data Source").Value = ServerName
> cn.Properties("Initial Catalog").Value = DatabaseName
> ' Windows NT authentication.
> cn.Properties("Integrated Security").Value = "SSPI"
> ' Open the database.
> cn.Open
> B. Using SQLOLEDB to connect to an instance of SQL Server: connection
> string method
> The following Visual Basic code fragment shows how to use SQLOLEDB to
> connect to an instance or SQL Server:
> ' Initialize variables.
> Dim cn As New ADODB.Connection
> Dim provStr As String
> ' Specify the OLE DB provider.
> cn.Provider = "sqloledb"
> ' Specify connection string on Open method.
> ProvStr = " Server=MyServer;Database=northwind;Trust
ed_Connection=yes"
> cn.Open provStr
> C. Using MSDASQL to connect to an instance of SQL Server
> To use MSDASQL to connect to an instance of SQL Server, use the following
> types of connections.
> The first type of connection is based on the ODBC API SQLConnect function.
> This type of connection is useful in situations where you do not want to
> code specific information about the data source. This may be the case if
> the data source could change or if you do not know its particulars.
> In the code fragment shown, the ConnectionTimeout method sets the
> connection time-out value to 100 seconds. Next, the data source name, and
> authentication type are passed as parameters to the Open method of the
> Connection object, using an ODBC data source named MyDataSource that point
s
> to the northwind database on an instance of SQL Server.
> Dim cn As New ADODB.Connection
> cn.ConnectionTimeout = 100
> ' DSN connection
> ' cn.Open " DSN=MyDataSource;Trusted_Connection=yes;
"
> cn.Close
> The second type of connection is based on the ODBC API SQLDriverConnect
> function. This type of connection is useful in situations where you want a
> driver-specific connection string. To make a connection, use the Open
> method of the Connection object and specify the driver, server name,
> authentication type, and database. You can also specify any other valid
> keywords to include in the connection string. For more information about
> the keyword list, see SQLDriverConnect.
> Dim cn As New ADODB.Connection
> ' Connection to SQL Server without using ODBC data source.
> cn.Open "Driver={SQL
> Server};Server=Server1;Database=northwin
d;Trusted_Connection=yes"
> cn.Close
> Using the Connection Object
> In addition to the Command object, an application can use the Connection
> object to issue commands, stored procedures, and user-defined functions to
> a database as if they were native methods on the Connection object. To
> execute a query without using a Command object, an application can pass a
> query string to the Execute method of a Connection object.
> However, a Command object is required if you want to save and re-execute
> the command text, or use query parameters.
> To execute a command on the Connection object
> Assign a name to the command using the Name property of the Command object
.
>
> Set the ActiveConnection property of the Command object to the connection.
>
> Issue a statement where the command name is used as if it were a method on
> the Connection object, followed by any parameters.
>
> Create a Recordset object if any rows are returned.
>
> Set the Recordset properties to customize the resulting Recordset.
> Using the Connection Object to Execute Commands
> This example shows how to use the Execute method of the Connection object
> to execute commands.
> Dim cn As New ADODB.Connection
> . . .
> Dim rs As New ADODB.Recordset
> cmd1 = txtQuery.Text
> Set rs = cn.Execute(cmd1)
> After the Connection and Recordset objects are created, the variable cmd1
> is assigned the value of a user-supplied query string (txtQuery.Text) from
> a Microsoft Visual Basic? form. The recordset is assigned the results of
a
> query, by calling the Execute method of the Connection object, with the
> variable cmd1 used as the query string parameter.
> Using the Recordset Object
> The Recordset object provides methods for manipulating result sets. It
> allows you to add, update, delete, and scroll through rows in the recordse
t.
> A Recordset object can be created using the Execute method of the
> Connection or Command object.
> Each row in a recordset can also be retrieved and updated using the Fields
> collection and the Field object. Updates on the Recordset object can be in
> an immediate or batch mode. When a Recordset object is created, a cursor i
s
> opened automatically.
> The Recordset object allows you to specify the cursor type and location fo
r
> fetching the result set. With the CursorType property, you can specify
> whether the cursor is read-only, forward-only, static, keyset-driven, or
> dynamic. Cursor type determines if a Recordset object can be scrolled or
> updated and affects the visibility of changed rows. By default, the cursor
> type is read-only and forward-only.
> An application can specify the location of the cursor with the
> CursorLocation property. This property allows you to specify whether to us
e
> a client or server cursor. The CursorLocation property setting is importan
t
> when you use disconnected recordsets.
> The first part of the cmdExecute_Click method in the ADO Introductory
> Visual Basic Sample shows an example of creating, opening, passing a
> command string variable to, and positioning the cursor in a recordset.
> Dim cn As New ADODB.Connection
> Dim rs As ADODB.Recordset
> . . .
> cmd1 = txtQuery.Text
> Set rs = New ADODB.Recordset
> rs.Open cmd1, cn
> rs.MoveFirst
> . . .
> ' Code to loop through result set(s)
> Thanks and regards,
> Girish Sundaram
>
> This posting is provided "AS IS" with no warranties, and confers no rights
.
>|||Ahmet, you could also look at www.asp.net. They have plenty of examples for
you on that site. You should be able to cut, paste, and modify.
"Ahmet Karaca" <AhmetKaraca@.discussions.microsoft.com> wrote in message
news:D99CE06D-E875-4084-919F-333C7840B6DC@.microsoft.com...[vbcol=seagreen]
> thank you for now
> I will try
> Probably I will turn back to you with some questions
> "Girish Sundaram" wrote:
>
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