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Procédure : télécharger des modifications de données incrémentielles sur un serveur

Cette rubrique décrit comment télécharger des modifications de données incrémentielles à partir d'une base de données client SQL Server Compact vers une base de données serveur. Les exemples de cette rubrique sont axés sur les types et les événements Sync Framework suivants :

Pour plus d'informations sur le mode d'exécution d'un exemple de code, consultez la section « Exemples d'application dans les rubriques de procédures » dans Programmation des tâches courantes de synchronisation client et serveur.

Exemple

L'exemple de code de cette rubrique indique comment configurer la synchronisation par téléchargement ascendant uniquement de la table Customer de l'exemple de base de données Sync Framework. Pour une vue d'ensemble des propriétés utilisées pour spécifier la direction de la synchronisation, consultez Procédure : spécifier la synchronisation par instantané, par téléchargement, par téléchargement ascendant et bidirectionnelle.

Pour la synchronisation par téléchargement ascendant uniquement, il est nécessaire que les modifications de données incrémentielles soient suivies dans la base de données client et appliquées à la base de données serveur. Sync Framework gère le suivi dans la base de données client. Cependant, vous devez spécifier les commandes qui appliquent les modifications à la base de données serveur, comme indiqué dans l'exemple de code.

Éléments clés de l'API

Cette section contient des exemples de code qui désignent les éléments clés de l'API utilisés pour la synchronisation par téléchargement ascendant uniquement. L'exemple de code suivant spécifie la direction de la synchronisation et la méthode de création de la table sur le client.

SyncTable customerSyncTable = new SyncTable("Customer");
customerSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
customerSyncTable.SyncDirection = SyncDirection.UploadOnly;
customerSyncTable.SyncGroup = customerSyncGroup;
this.Configuration.SyncTables.Add(customerSyncTable);
Dim customerSyncTable As New SyncTable("Customer")
customerSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
customerSyncTable.SyncDirection = SyncDirection.UploadOnly
customerSyncTable.SyncGroup = customerSyncGroup
Me.Configuration.SyncTables.Add(customerSyncTable)

L'exemple de code suivant spécifie une commande permettant d'extraire une nouvelle valeur d'ancre à partir du serveur. Dans ce cas, une valeur d'horodatage est extraite et stockée dans la base de données client. Lors de chaque session de synchronisation, la valeur d'ancre est utilisée pour garantir que les modifications téléchargées ne remplacent pas celles qui ont été effectuées au niveau du serveur depuis la dernière session de synchronisation.

SqlCommand selectNewAnchorCommand = new SqlCommand();
string newAnchorVariable = "@" + SyncSession.SyncNewReceivedAnchor;
selectNewAnchorCommand.CommandText =
    "SELECT " + newAnchorVariable + " = min_active_rowversion() - 1";
selectNewAnchorCommand.Parameters.Add(newAnchorVariable, SqlDbType.Timestamp);
selectNewAnchorCommand.Parameters[newAnchorVariable].Direction = ParameterDirection.Output;
selectNewAnchorCommand.Connection = serverConn;
this.SelectNewAnchorCommand = selectNewAnchorCommand;
Dim selectNewAnchorCommand As New SqlCommand()
Dim newAnchorVariable As String = "@" + SyncSession.SyncNewReceivedAnchor
With selectNewAnchorCommand
    .CommandText = "SELECT " + newAnchorVariable + " = min_active_rowversion() - 1"
    .Parameters.Add(newAnchorVariable, SqlDbType.Timestamp)
    .Parameters(newAnchorVariable).Direction = ParameterDirection.Output
    .Connection = serverConn
End With
Me.SelectNewAnchorCommand = selectNewAnchorCommand

L'exemple de code suivant spécifie une commande permettant d'obtenir le schéma à partir de la base de données serveur. Avec la synchronisation par téléchargement ascendant uniquement, cette commande n'obtient pas les données à partir de la base de données serveur (ce qui n'est pas le cas des autres types de synchronisation).

SqlCommand customerIncrInserts = new SqlCommand();
customerIncrInserts.CommandText =
    "SELECT CustomerId, CustomerName, SalesPerson, CustomerType " +
    "FROM Sales.Customer";
customerIncrInserts.Connection = serverConn;
customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts;
Dim customerIncrInserts As New SqlCommand()
With customerIncrInserts
    .CommandText = _
        "SELECT CustomerId, CustomerName, SalesPerson, CustomerType " _
      & "FROM Sales.Customer"
    .Connection = serverConn            
End With
customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts

L'exemple de code suivant spécifie une commande permettant d'appliquer les mises à jour du client au serveur. Il s'agit d'une instruction UPDATE qui inclut les colonnes à mettre à jour. Il existe une clause WHERE qui utilise la valeur d'ancre que la propriété SelectNewAnchorCommand récupère, ainsi que l'ID de client. La clause WHERE inclut également @sync\_force\_write = 1. Ce paramètre force l'application des mises à jour conflictuelles. Pour plus d'informations sur @sync\_force\_write et d'autres variables de session, consultez Procédure : utiliser des variables de session.

SqlCommand customerUpdates = new SqlCommand();
customerUpdates.CommandText =
    "UPDATE Sales.Customer SET " +
    "CustomerName = @CustomerName, SalesPerson = @SalesPerson, " +
    "CustomerType = @CustomerType, " +
    "UpdateId = @sync_client_id " +
    "WHERE (CustomerId = @CustomerId) " +
    "AND (@sync_force_write = 1 " +
    "OR (UpdateTimestamp <= @sync_last_received_anchor " +
    "OR UpdateId = @sync_client_id)) " +
    "SET @sync_row_count = @@rowcount";
customerUpdates.Parameters.Add("@CustomerName", SqlDbType.NVarChar);
customerUpdates.Parameters.Add("@SalesPerson", SqlDbType.NVarChar);
customerUpdates.Parameters.Add("@CustomerType", SqlDbType.NVarChar);
customerUpdates.Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier);
customerUpdates.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
customerUpdates.Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit);
customerUpdates.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
customerUpdates.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);
customerUpdates.Connection = serverConn;
customerSyncAdapter.UpdateCommand = customerUpdates;
Dim customerUpdates As New SqlCommand()
With customerUpdates
    .CommandText = _
        "UPDATE Sales.Customer SET " _
      & "CustomerName = @CustomerName, SalesPerson = @SalesPerson, " _
      & "CustomerType = @CustomerType, " _
      & "UpdateId = @sync_client_id " _
      & "WHERE (CustomerId = @CustomerId) " _
      & "AND (@sync_force_write = 1 " _
      & "OR (UpdateTimestamp <= @sync_last_received_anchor " _
      & "OR UpdateId = @sync_client_id)) " _
      & "SET @sync_row_count = @@rowcount"
    .Parameters.Add("@CustomerName", SqlDbType.NVarChar)
    .Parameters.Add("@SalesPerson", SqlDbType.NVarChar)
    .Parameters.Add("@CustomerType", SqlDbType.NVarChar)
    .Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier)
    .Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
    .Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit)
    .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
    .Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int)
    .Connection = serverConn
End With
customerSyncAdapter.UpdateCommand = customerUpdates

Exemple de code complet

L'exemple de code complet ci-dessous inclut les exemples de code décrits précédemment, ainsi que du code supplémentaire pour effectuer la synchronisation. Examinez également la manière dont SyncStatistics est utilisé pour afficher des informations sur la session de synchronisation, ainsi que le mode d'utilisation des événements CreatingSchema et SchemaCreated pour ajouter une valeur par défaut pour la colonne CustomerId. L'exemple requiert la classe Utility qui est disponible dans Classe d'utilitaire pour les rubriques de procédures sur le fournisseur de bases de données.

using System;
using System.IO;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlServerCe;
using Microsoft.Synchronization;
using Microsoft.Synchronization.Data;
using Microsoft.Synchronization.Data.Server;
using Microsoft.Synchronization.Data.SqlServerCe;

namespace Microsoft.Samples.Synchronization
{
    class Program
    {
        static void Main(string[] args)
        {

            //The SampleStats class handles information from the SyncStatistics
            //object that the Synchronize method returns.
            SampleStats sampleStats = new SampleStats();

            //Request a password for the client database, and delete
            //and re-create the database. The client synchronization
            //provider also enables you to create the client database 
            //if it does not exist.
            Utility.SetPassword_SqlCeClientSync();
            Utility.DeleteAndRecreateCompactDatabase(Utility.ConnStr_SqlCeClientSync, true);

            //Initial synchronization. Instantiate the SyncAgent
            //and call Synchronize.
            SampleSyncAgent sampleSyncAgent = new SampleSyncAgent();
            SyncStatistics syncStatistics = sampleSyncAgent.Synchronize();
            sampleStats.DisplayStats(syncStatistics, "initial");

            //Make changes on the client.
            Utility.MakeDataChangesOnClient("Customer");

            //Subsequent synchronization.
            syncStatistics = sampleSyncAgent.Synchronize();
            sampleStats.DisplayStats(syncStatistics, "subsequent");

            //Return server data back to its original state.
            Utility.CleanUpServer();

            //Exit.
            Console.Write("\nPress Enter to close the window.");
            Console.ReadLine();
        }
    }

    //Create a class that is derived from 
    //Microsoft.Synchronization.SyncAgent.
    public class SampleSyncAgent : SyncAgent
    {
        public SampleSyncAgent()
        {
            //Instantiate a client synchronization provider and specify it
            //as the local provider for this synchronization agent.
            this.LocalProvider = new SampleClientSyncProvider();

            //Instantiate a server synchronization provider and specify it
            //as the remote provider for this synchronization agent.
            this.RemoteProvider = new SampleServerSyncProvider();

            //Create a Customer SyncGroup. This is not required
            //for the single table that we are synchronizing. It is typically
            //used so that changes to multiple related tables are 
            //synchronized at the same time.
            SyncGroup customerSyncGroup = new SyncGroup("Customer");

            //Add the Customer table: specify a synchronization direction of
            //UploadOnly, and that an existing table should be dropped.
            SyncTable customerSyncTable = new SyncTable("Customer");
            customerSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
            customerSyncTable.SyncDirection = SyncDirection.UploadOnly;
            customerSyncTable.SyncGroup = customerSyncGroup;
            this.Configuration.SyncTables.Add(customerSyncTable);
        }
    }

    //Create a class that is derived from 
    //Microsoft.Synchronization.Server.DbServerSyncProvider.
    public class SampleServerSyncProvider : DbServerSyncProvider
    {
        public SampleServerSyncProvider()
        {
            //Create a connection to the sample server database.
            Utility util = new Utility();
            SqlConnection serverConn = new SqlConnection(Utility.ConnStr_DbServerSync);
            this.Connection = serverConn;

            //Create a command to retrieve a new anchor value from
            //the server. In this case, we use a timestamp value
            //that is retrieved and stored in the client database.
            //During each synchronization, the new anchor value and
            //the last anchor value from the previous synchronization
            //are used: the set of changes between these upper and
            //lower bounds is synchronized.
            //
            //SyncSession.SyncNewReceivedAnchor is a string constant; 
            //you could also use @sync_new_received_anchor directly in 
            //your queries.
            SqlCommand selectNewAnchorCommand = new SqlCommand();
            string newAnchorVariable = "@" + SyncSession.SyncNewReceivedAnchor;
            selectNewAnchorCommand.CommandText =
                "SELECT " + newAnchorVariable + " = min_active_rowversion() - 1";
            selectNewAnchorCommand.Parameters.Add(newAnchorVariable, SqlDbType.Timestamp);
            selectNewAnchorCommand.Parameters[newAnchorVariable].Direction = ParameterDirection.Output;
            selectNewAnchorCommand.Connection = serverConn;
            this.SelectNewAnchorCommand = selectNewAnchorCommand;

            //Create a SyncAdapter for the Customer table, and then define
            //the commands to synchronize changes:
            //* SelectIncrementalInsertsCommand is used to get the schema
            //  from the server.
            //* InsertCommand, UpdateCommand, and DeleteCommand are used to apply
            //  to the server the changes that the client provider has selected
            //  from the client.

            //Create the SyncAdapter.
            SyncAdapter customerSyncAdapter = new SyncAdapter("Customer");

            //Get the schema from the server.
            SqlCommand customerIncrInserts = new SqlCommand();
            customerIncrInserts.CommandText =
                "SELECT CustomerId, CustomerName, SalesPerson, CustomerType " +
                "FROM Sales.Customer";
            customerIncrInserts.Connection = serverConn;
            customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts;

            //Apply inserts to the server.
            SqlCommand customerInserts = new SqlCommand();
            customerInserts.CommandText =
                "INSERT INTO Sales.Customer (CustomerId, CustomerName, SalesPerson, CustomerType, InsertId, UpdateId) " +
                "VALUES (@CustomerId, @CustomerName, @SalesPerson, @CustomerType, @sync_client_id, @sync_client_id) " +
                "SET @sync_row_count = @@rowcount";
            customerInserts.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
            customerInserts.Parameters.Add("@CustomerName", SqlDbType.NVarChar);
            customerInserts.Parameters.Add("@SalesPerson", SqlDbType.NVarChar);
            customerInserts.Parameters.Add("@CustomerType", SqlDbType.NVarChar);
            customerInserts.Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier);
            customerInserts.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);
            customerInserts.Connection = serverConn;
            customerSyncAdapter.InsertCommand = customerInserts;

            //Apply updates to the server.
            SqlCommand customerUpdates = new SqlCommand();
            customerUpdates.CommandText =
                "UPDATE Sales.Customer SET " +
                "CustomerName = @CustomerName, SalesPerson = @SalesPerson, " +
                "CustomerType = @CustomerType, " +
                "UpdateId = @sync_client_id " +
                "WHERE (CustomerId = @CustomerId) " +
                "AND (@sync_force_write = 1 " +
                "OR (UpdateTimestamp <= @sync_last_received_anchor " +
                "OR UpdateId = @sync_client_id)) " +
                "SET @sync_row_count = @@rowcount";
            customerUpdates.Parameters.Add("@CustomerName", SqlDbType.NVarChar);
            customerUpdates.Parameters.Add("@SalesPerson", SqlDbType.NVarChar);
            customerUpdates.Parameters.Add("@CustomerType", SqlDbType.NVarChar);
            customerUpdates.Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier);
            customerUpdates.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
            customerUpdates.Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit);
            customerUpdates.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
            customerUpdates.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);
            customerUpdates.Connection = serverConn;
            customerSyncAdapter.UpdateCommand = customerUpdates;

            //Apply deletes to the server.            
            SqlCommand customerDeletes = new SqlCommand();
            customerDeletes.CommandText =
                "DELETE FROM Sales.Customer " +
                "WHERE (CustomerId = @CustomerId) " +
                "AND (@sync_force_write = 1 " +
                "OR (UpdateTimestamp <= @sync_last_received_anchor " +
                "OR UpdateId = @sync_client_id)) " +
                "SET @sync_row_count = @@rowcount " +
                "IF (@sync_row_count > 0)  BEGIN " +
                "UPDATE Sales.Customer_Tombstone " +
                "SET DeleteId = @sync_client_id " +
                "WHERE (CustomerId = @CustomerId) " +
                "END";
            customerDeletes.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
            customerDeletes.Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit);
            customerDeletes.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
            customerDeletes.Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier);
            customerDeletes.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);
            customerDeletes.Connection = serverConn;
            customerSyncAdapter.DeleteCommand = customerDeletes;

            //Add the SyncAdapter to the server synchronization provider.
            this.SyncAdapters.Add(customerSyncAdapter);

        }
    }

    //Create a class that is derived from 
    //Microsoft.Synchronization.Data.SqlServerCe.SqlCeClientSyncProvider.
    //You can just instantiate the provider directly and associate it
    //with the SyncAgent, but here we use this class to handle client 
    //provider events.
    public class SampleClientSyncProvider : SqlCeClientSyncProvider
    {

        public SampleClientSyncProvider()
        {
            //Specify a connection string for the sample client database.
            Utility util = new Utility();
            this.ConnectionString = Utility.ConnStr_SqlCeClientSync;

            //We use the CreatingSchema event to change the schema
            //by using the API. We use the SchemaCreated event to 
            //change the schema by using SQL.
            this.CreatingSchema += new EventHandler<CreatingSchemaEventArgs>(SampleClientSyncProvider_CreatingSchema);
            this.SchemaCreated += new EventHandler<SchemaCreatedEventArgs>(SampleClientSyncProvider_SchemaCreated);
        }

        private void SampleClientSyncProvider_CreatingSchema(object sender, CreatingSchemaEventArgs e)
        {
            //Set the RowGuid property because it is not copied
            //to the client by default. This is also a good time
            //to specify literal defaults with .Columns[ColName].DefaultValue,
            //but we will specify defaults like NEWID() by calling
            //ALTER TABLE after the table is created.
            Console.Write("Creating schema for " + e.Table.TableName + " | ");
            e.Schema.Tables["Customer"].Columns["CustomerId"].RowGuid = true;
        }

        private void SampleClientSyncProvider_SchemaCreated(object sender, SchemaCreatedEventArgs e)
        {
            //Call ALTER TABLE on the client. This must be done
            //over the same connection and within the same
            //transaction that Sync Framework uses
            //to create the schema on the client.
            Utility util = new Utility();
            Utility.MakeSchemaChangesOnClient(e.Connection, e.Transaction, e.Table.TableName);
            Console.WriteLine("Schema created for " + e.Table.TableName);
        }
    }

    //Handle the statistics that are returned by the SyncAgent.
    public class SampleStats
    {
        public void DisplayStats(SyncStatistics syncStatistics, string syncType)
        {
            Console.WriteLine(String.Empty);
            if (syncType == "initial")
            {
                Console.WriteLine("****** Initial Synchronization ******");
            }
            else if (syncType == "subsequent")
            {
                Console.WriteLine("***** Subsequent Synchronization ****");
            }

            Console.WriteLine("Start Time: " + syncStatistics.SyncStartTime);
            Console.WriteLine("Total Changes Uploaded: " + syncStatistics.TotalChangesUploaded);
            Console.WriteLine("Total Changes Downloaded: " + syncStatistics.TotalChangesDownloaded);
            Console.WriteLine("Complete Time: " + syncStatistics.SyncCompleteTime);
            Console.WriteLine(String.Empty);
        }
    }
}
Imports System
Imports System.IO
Imports System.Text
Imports System.Data
Imports System.Data.SqlClient
Imports System.Data.SqlServerCe
Imports Microsoft.Synchronization
Imports Microsoft.Synchronization.Data
Imports Microsoft.Synchronization.Data.Server
Imports Microsoft.Synchronization.Data.SqlServerCe

Class Program

    Shared Sub Main(ByVal args() As String)

        'The SampleStats class handles information from the SyncStatistics
        'object that the Synchronize method returns.
        Dim sampleStats As New SampleStats()

        'Request a password for the client database, and delete
        'and re-create the database. The client synchronization
        'provider also enables you to create the client database 
        'if it does not exist.
        Utility.SetPassword_SqlCeClientSync()
        Utility.DeleteAndRecreateCompactDatabase(Utility.ConnStr_SqlCeClientSync, True)

        'Initial synchronization. Instantiate the SyncAgent
        'and call Synchronize.
        Dim sampleSyncAgent As New SampleSyncAgent()
        Dim syncStatistics As SyncStatistics = sampleSyncAgent.Synchronize()
        sampleStats.DisplayStats(syncStatistics, "initial")

        'Make changes on the client.
        Utility.MakeDataChangesOnClient("Customer")

        'Subsequent synchronization.
        syncStatistics = sampleSyncAgent.Synchronize()
        sampleStats.DisplayStats(syncStatistics, "subsequent")

        'Return server data back to its original state.
        Utility.CleanUpServer()

        'Exit.
        Console.Write(vbLf + "Press Enter to close the window.")
        Console.ReadLine()

    End Sub 'Main
End Class 'Program

'Create a class that is derived from 
'Microsoft.Synchronization.SyncAgent.
Public Class SampleSyncAgent
    Inherits SyncAgent

    Public Sub New()
        'Instantiate a client synchronization provider and specify it
        'as the local provider for this synchronization agent.
        Me.LocalProvider = New SampleClientSyncProvider()

        'Instantiate a server synchronization provider and specify it
        'as the remote provider for this synchronization agent.
        Me.RemoteProvider = New SampleServerSyncProvider()

        'Create a Customer SyncGroup. This is not required
        'for the single table that we are synchronizing. It is typically
        'used so that changes to multiple related tables are 
        'synchronized at the same time.
        Dim customerSyncGroup As New SyncGroup("Customer")

        'Add the Customer table: specify a synchronization direction of
        'UploadOnly, and that an existing table should be dropped.
        Dim customerSyncTable As New SyncTable("Customer")
        customerSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
        customerSyncTable.SyncDirection = SyncDirection.UploadOnly
        customerSyncTable.SyncGroup = customerSyncGroup
        Me.Configuration.SyncTables.Add(customerSyncTable)

    End Sub 'New
End Class 'SampleSyncAgent

'Create a class that is derived from 
'Microsoft.Synchronization.Server.DbServerSyncProvider.
Public Class SampleServerSyncProvider
    Inherits DbServerSyncProvider

    Public Sub New()
        'Create a connection to the sample server database.
        Dim util As New Utility()
        Dim serverConn As New SqlConnection(Utility.ConnStr_DbServerSync)
        Me.Connection = serverConn

        'Create a command to retrieve a new anchor value from
        'the server. In this case, we use a timestamp value
        'that is retrieved and stored in the client database.
        'During each synchronization, the new anchor value and
        'the last anchor value from the previous synchronization
        'are used: the set of changes between these upper and
        'lower bounds is synchronized.
        '
        'SyncSession.SyncNewReceivedAnchor is a string constant; 
        'you could also use @sync_new_received_anchor directly in 
        'your queries.
        Dim selectNewAnchorCommand As New SqlCommand()
        Dim newAnchorVariable As String = "@" + SyncSession.SyncNewReceivedAnchor
        With selectNewAnchorCommand
            .CommandText = "SELECT " + newAnchorVariable + " = min_active_rowversion() - 1"
            .Parameters.Add(newAnchorVariable, SqlDbType.Timestamp)
            .Parameters(newAnchorVariable).Direction = ParameterDirection.Output
            .Connection = serverConn
        End With
        Me.SelectNewAnchorCommand = selectNewAnchorCommand

        'Create a SyncAdapter for the Customer table, and then define
        'the commands to synchronize changes:
        '* SelectIncrementalInsertsCommand is used to get the schema
        '  from the server.
        '* InsertCommand, UpdateCommand, and DeleteCommand are used to apply
        '  to the server the changes that the client provider has selected
        '  from the client.

        'Create the SyncAdapter.
        Dim customerSyncAdapter As New SyncAdapter("Customer")

        'Get the schema from the server.
        Dim customerIncrInserts As New SqlCommand()
        With customerIncrInserts
            .CommandText = _
                "SELECT CustomerId, CustomerName, SalesPerson, CustomerType " _
              & "FROM Sales.Customer"
            .Connection = serverConn            
        End With
        customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts

        'Apply inserts to the server.
        Dim customerInserts As New SqlCommand()
        With customerInserts
            .CommandText = _
               "INSERT INTO Sales.Customer (CustomerId, CustomerName, SalesPerson, CustomerType, InsertId, UpdateId) " _
             & "VALUES (@CustomerId, @CustomerName, @SalesPerson, @CustomerType, @sync_client_id, @sync_client_id) " _
             & "SET @sync_row_count = @@rowcount"
            .Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
            .Parameters.Add("@CustomerName", SqlDbType.NVarChar)
            .Parameters.Add("@SalesPerson", SqlDbType.NVarChar)
            .Parameters.Add("@CustomerType", SqlDbType.NVarChar)
            .Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier)
            .Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int)
            .Connection = serverConn
        End With
        customerSyncAdapter.InsertCommand = customerInserts

        'Apply updates to the server.
        Dim customerUpdates As New SqlCommand()
        With customerUpdates
            .CommandText = _
                "UPDATE Sales.Customer SET " _
              & "CustomerName = @CustomerName, SalesPerson = @SalesPerson, " _
              & "CustomerType = @CustomerType, " _
              & "UpdateId = @sync_client_id " _
              & "WHERE (CustomerId = @CustomerId) " _
              & "AND (@sync_force_write = 1 " _
              & "OR (UpdateTimestamp <= @sync_last_received_anchor " _
              & "OR UpdateId = @sync_client_id)) " _
              & "SET @sync_row_count = @@rowcount"
            .Parameters.Add("@CustomerName", SqlDbType.NVarChar)
            .Parameters.Add("@SalesPerson", SqlDbType.NVarChar)
            .Parameters.Add("@CustomerType", SqlDbType.NVarChar)
            .Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier)
            .Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
            .Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit)
            .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int)
            .Connection = serverConn
        End With
        customerSyncAdapter.UpdateCommand = customerUpdates

        'Apply deletes to the server.            
        Dim customerDeletes As New SqlCommand()
        With customerDeletes
            .CommandText = _
                "DELETE FROM Sales.Customer " _
              & "WHERE (CustomerId = @CustomerId) " _
              & "AND (@sync_force_write = 1 " _
              & "OR (UpdateTimestamp <= @sync_last_received_anchor " _
              & "OR UpdateId = @sync_client_id)) " _
              & "SET @sync_row_count = @@rowcount " _
              & "IF (@sync_row_count > 0)  BEGIN " _
              & "UPDATE Sales.Customer_Tombstone " _
              & "SET DeleteId = @sync_client_id " _
              & "WHERE (CustomerId = @CustomerId) " _
              & "END"
            .Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
            .Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit)
            .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier)
            .Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int)
            .Connection = serverConn
        End With
        customerSyncAdapter.DeleteCommand = customerDeletes

        'Add the SyncAdapter to the server synchronization provider.
        Me.SyncAdapters.Add(customerSyncAdapter)

    End Sub 'New 
End Class 'SampleServerSyncProvider

'Create a class that is derived from 
'Microsoft.Synchronization.Data.SqlServerCe.SqlCeClientSyncProvider.
'You can just instantiate the provider directly and associate it
'with the SyncAgent, but here we use this class to handle client 
'provider events.
Public Class SampleClientSyncProvider
    Inherits SqlCeClientSyncProvider


    Public Sub New()
        'Specify a connection string for the sample client database.
        Dim util As New Utility()
        Me.ConnectionString = Utility.ConnStr_SqlCeClientSync

        'We use the CreatingSchema event to change the schema
        'by using the API. We use the SchemaCreated event to 
        'change the schema by using SQL.
        AddHandler Me.CreatingSchema, AddressOf SampleClientSyncProvider_CreatingSchema
        AddHandler Me.SchemaCreated, AddressOf SampleClientSyncProvider_SchemaCreated
    End Sub 'New


    Private Sub SampleClientSyncProvider_CreatingSchema(ByVal sender As Object, ByVal e As CreatingSchemaEventArgs)
        'Set the RowGuid property because it is not copied
        'to the client by default. This is also a good time
        'to specify literal defaults with .Columns[ColName].DefaultValue,
        'but we will specify defaults like NEWID() by calling
        'ALTER TABLE after the table is created.
        Console.Write("Creating schema for " + e.Table.TableName + " | ")
        e.Schema.Tables("Customer").Columns("CustomerId").RowGuid = True

    End Sub 'SampleClientSyncProvider_CreatingSchema


    Private Sub SampleClientSyncProvider_SchemaCreated(ByVal sender As Object, ByVal e As SchemaCreatedEventArgs)
        'Call ALTER TABLE on the client. This must be done
        'over the same connection and within the same
        'transaction that Sync Framework uses
        'to create the schema on the client.
        Dim util As New Utility()
        Utility.MakeSchemaChangesOnClient(e.Connection, e.Transaction, e.Table.TableName)
        Console.WriteLine("Schema created for " + e.Table.TableName)

    End Sub 'SampleClientSyncProvider_SchemaCreated
End Class 'SampleClientSyncProvider

'Handle the statistics that are returned by the SyncAgent.
Public Class SampleStats

    Public Sub DisplayStats(ByVal syncStatistics As SyncStatistics, ByVal syncType As String)
        Console.WriteLine(String.Empty)
        If syncType = "initial" Then
            Console.WriteLine("****** Initial Synchronization ******")
        ElseIf syncType = "subsequent" Then
            Console.WriteLine("***** Subsequent Synchronization ****")
        End If

        Console.WriteLine("Start Time: " & syncStatistics.SyncStartTime)
        Console.WriteLine("Total Changes Uploaded: " & syncStatistics.TotalChangesUploaded)
        Console.WriteLine("Total Changes Downloaded: " & syncStatistics.TotalChangesDownloaded)
        Console.WriteLine("Complete Time: " & syncStatistics.SyncCompleteTime)
        Console.WriteLine(String.Empty)

    End Sub 'DisplayStats
End Class 'SampleStats

Voir aussi

Autres ressources

Architecture et classes pour la synchronisation client et serveur

Procédure : spécifier la synchronisation par instantané, par téléchargement, par téléchargement ascendant et bidirectionnelle