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Menjalankan Updategram dengan Menggunakan ADO (SQLXML 4.0)

Aplikasi Microsoft Visual Basic ini menggunakan ADO untuk membuat koneksi ke instans Microsoft SQL Server dan menjalankan pembaruangram. Updategram memperbarui nama belakang karyawan tertentu. Contoh ini menggunakan database sampel AdventureWorks.

Dalam aplikasi sampel ini:

  • Objek conn (ADODB. Koneksi) membuat koneksi ke instans SQL Server yang sedang berjalan pada komputer server tertentu.

  • Objek cmd (ADODB. Perintah) dijalankan pada koneksi yang dibuat.

  • Dialek perintah diatur ke DBGUID_MSSQLXML.

  • Updategram disalin ke aliran perintah (strmIn).

  • Aliran output perintah diatur ke objek StrmOut (ADODB. Stream) untuk menerima data yang dikembalikan.

  • Akhirnya perintah (updategram) dijalankan.

Berikut adalah kode sampel:

Private Sub Form_Load()  
  
  Dim cmd As New ADODB.Command  
  Dim conn As New ADODB.Connection  
  Dim strmIn As New ADODB.Stream  
  Dim strmOut As New ADODB.Stream  
  Dim SQLxml As String  
  
  ' Open a connection to the instance of SQL Server.  
  conn.Provider = "SQLOLEDB"  
  conn.Open "server=(local); database=AdventureWorks; Integrated Security=SSPI; "  
  conn.Properties("SQLXML Version") = "SQLXML.4.0"  
  Set cmd.ActiveConnection = conn  
  
  ' Build the command string in the form of an XML template.  
    SQLxml = "<ROOT xmlns:updg='urn:schemas-microsoft-com:xml-updategram' >"  
    SQLxml = SQLxml & "  <updg:sync updg:nullvalue='IsNULL'>"  
    SQLxml = SQLxml & "    <updg:before>"  
    SQLxml = SQLxml & "       <Person.Contact ContactID='64' Title='IsNULL'/>"  
    SQLxml = SQLxml & "    </updg:before>"  
    SQLxml = SQLxml & "    <updg:after>"  
    SQLxml = SQLxml & "       <Person.Contact ContactID='64' Title='Mr.'/>"  
    SQLxml = SQLxml & "    </updg:after>"  
    SQLxml = SQLxml & "  </updg:sync>"  
    SQLxml = SQLxml & "</ROOT>"  
  
  ' Set the command dialect to DBGUID_MSSQLXML.  
  cmd.Dialect = "{5d531cb2-e6ed-11d2-b252-00c04f681b71}"  
  
  ' Open the command stream and write our template to it.  
  strmIn.Open  
  strmIn.WriteText SQLxml  
  strmIn.Position = 0  
  
  Set cmd.CommandStream = strmIn  
  
  ' Execute the command, open the return stream, and read the result.  
  strmOut.Open  
  strmOut.LineSeparator = adCRLF  
  cmd.Properties("Output Stream").Value = strmOut  
  cmd.Properties("Output Encoding").Value = "UTF-8"  
  cmd.Execute , , adExecuteStream  
  strmOut.Position = 0  
  Debug.Print strmOut.ReadText  
  strmOut.Close  
  strmIn.Close  
  
End Sub  
  

Nota

Jika Anda menggunakan SQLXML dari ADO untuk menjalankan updategram yang menentukan skema XSD, Anda harus mengatur properti "SQLXML Version" ke "SQLXML.4.0" pada objek koneksi, seperti yang ditunjukkan dalam baris contoh kode berikut:

conn.Properties("SQLXML Version") = "SQLXML.4.0"

Menentukan Skema Pemetaan untuk Updategram

Contoh ini menggambarkan cara menentukan dan menggunakan skema pemetaan dalam updategram.

Simpan skema XSD berikut (EmpSchema.xml) ke disk Anda, dan pastikan untuk memperbarui jalur yang ditentukan dalam kode ke lokasi skema pemetaan pada disk Anda. Kode mengasumsikan bahwa skema disimpan pada drive C: di folder Skema.

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"  
            xmlns:sql="urn:schemas-microsoft-com:mapping-schema">  
  <xsd:element name="Contact" sql:relation="Person.Contact" >  
   <xsd:complexType>  
        <xsd:attribute name="CID"    
                       sql:field="ContactID"   
                       type="xsd:string" />   
        <xsd:attribute name="MName"    
                       sql:field="MiddleName"    
                       type="xsd:string" />  
    </xsd:complexType>  
  </xsd:element>  
</xsd:schema>  

Karena skema XSD dan XDR dapat ditentukan, ini adalah skema XDR yang setara:

<?xml version="1.0" ?>  
   <Schema xmlns="urn:schemas-microsoft-com:xml-data"   
         xmlns:dt="urn:schemas-microsoft-com:datatypes"   
         xmlns:sql="urn:schemas-microsoft-com:xml-sql">  
     <ElementType name="Contact" sql:relation="Person.Contact" >  
       <AttributeType name="CID" />  
       <AttributeType name="MName" />  
  
       <attribute type="CID" sql:field="ContactID" />  
       <attribute type="MName" sql:field="MiddleName" />  
     </ElementType>  
   </Schema>   

Ini adalah kode Visual Basic untuk menjalankan updategram yang memiliki skema pemetaan terkait. Updategram memperbarui nama tengah untuk kontak 1 di tabel Person.Contact.

Private Sub Form_Load()  
    Dim cmd As New ADODB.Command  
    Dim conn As New ADODB.Connection  
    Dim strmIn As New ADODB.Stream  
    Dim strmOut As New ADODB.Stream  
  
    ' Open a connection to the SQL Server.  
    conn.Provider = "SQLOLEDB"  
    conn.Open "server=(local); database=AdventureWorks; Integrated Security='SSPI' ;"  
    conn.Properties("SQLXML Version") = "SQLXML.4.0"  
    Set cmd.ActiveConnection = conn  
  
    ' Open the command stream and write the template to it.  
    strmIn.Open  
    strmIn.WriteText "<ROOT xmlns:updg='urn:schemas-microsoft-com:xml-updategram' >"  
    strmIn.WriteText "  <updg:sync mapping-schema='C:\Schemas\EmpSchema.xml' >"  
    strmIn.WriteText "      <updg:before>"  
    strmIn.WriteText "          <Contact CID='1' />"  
    strmIn.WriteText "      </updg:before>"  
    strmIn.WriteText "      <updg:after>"  
    strmIn.WriteText "          <Contact MName='M.'/>"  
    strmIn.WriteText "      </updg:after>"  
    strmIn.WriteText "  </updg:sync>"  
    strmIn.WriteText "</ROOT>"  
  
    ' Set the command dialect to XML.  
    cmd.Dialect = "{5d531cb2-e6ed-11d2-b252-00c04f681b71}"  
    strmIn.Position = 0  
    Set cmd.CommandStream = strmIn  
  
    ' Execute the command, open the return stream, and read the result.  
    strmOut.Open  
    strmOut.LineSeparator = adCRLF  
    cmd.Properties("Output Stream").Value = strmOut  
    cmd.Execute , , adExecuteStream  
    strmOut.Position = 0  
    Debug.Print strmOut.ReadText  
    strmOut.Close  
    strmIn.Close  
    conn.Close  
End Sub  

Meneruskan Parameter

Dalam aplikasi Visual Basic yang disediakan sebelumnya, parameter tidak diteruskan. Dalam aplikasi ini, nilai ContactID dan MiddleName diteruskan sebagai input parameter ke updategram.

Private Sub Form_Load()  
  
  Dim cmd As New ADODB.Command  
  Dim conn As New ADODB.Connection  
  Dim strmIn As New ADODB.Stream  
  Dim strmOut As New ADODB.Stream  
  Dim InputContactID As String  
  Dim InputMiddleName As String  
  
  InputContactID = "1"  
  InputMiddleName = "Q."  
  
  ' Open a connection to the instance of SQL Server.  
  conn.Provider = "SQLOLEDB"  
  conn.Open "server=(local); database=AdventureWorks; Integrated Security=SSPI; "  
  conn.Properties("SQLXML Version") = "SQLXML.4.0"  
  Set cmd.ActiveConnection = conn  
  
  ' Build the command string in the form of an XML template.  
  SQLxml = "<ROOT xmlns:updg='urn:schemas-microsoft-com:xml-updategram' >"  
  SQLxml = SQLxml & "<updg:header>"  
  SQLxml = SQLxml & "<updg:param name='ContactID'/>"  
  SQLxml = SQLxml & "<updg:param name='MiddleName' />"  
  SQLxml = SQLxml & "</updg:header>"  
  SQLxml = SQLxml & "<updg:sync >"  
  SQLxml = SQLxml & " <updg:before>"  
  SQLxml = SQLxml & "   <Person.Contact ContactID='$ContactID' />"  
  SQLxml = SQLxml & "</updg:before>"  
  SQLxml = SQLxml & "<updg:after>"  
  SQLxml = SQLxml & "<Person.Contact MiddleName='$MiddleName' />"  
  SQLxml = SQLxml & "</updg:after>"  
  SQLxml = SQLxml & "</updg:sync>"  
  SQLxml = SQLxml & "</ROOT>"  
  
  ' Set the command dialect to XML.  
  cmd.Dialect = "{5d531cb2-e6ed-11d2-b252-00c04f681b71}"  
  
  ' Open the command stream and write the template to it.  
  strmIn.Open  
  strmIn.WriteText SQLxml  
  strmIn.Position = 0  
  
  Set cmd.CommandStream = strmIn  
  
  ' Execute the command, open the return stream, and read the result.  
  strmOut.Open  
  strmOut.LineSeparator = adCRLF  
  cmd.NamedParameters = True  
  cmd.Parameters.Append cmd.CreateParameter("@ContactID", adBSTR, adParamInput, 1, InputContactID)  
  cmd.Parameters.Append cmd.CreateParameter("@MiddleName", adBSTR, adParamInput, 7, InputMiddleName)  
  cmd.Properties("Output Stream").Value = strmOut  
  cmd.Execute , , adExecuteStream  
  strmOut.Position = 0  
  Debug.Print strmOut.ReadText  
  
End Sub