如何将增量数据变更上载到服务器

项目
10/19/2009

本主题演示如何将 SQL Server Compact 客户端数据库中的增量数据变更上载到服务器数据库。本主题中的示例着重介绍以下 Sync Framework 类型和事件：

有关如何运行示例代码的信息，请参见对常见客户端与服务器同步任务进行编程中的“帮助主题中的示例应用程序”。

示例

本主题中的示例代码演示如何为 Sync Framework 示例数据库中的 Customer 表配置仅限上载同步。有关用于指定同步方向的属性的概述，请参见如何指定快照同步、下载同步、上载同步和双向同步。

仅上载同步要求在客户端数据库中跟踪增量数据变更并将这些变更应用于服务器数据库。Sync Framework 负责处理在客户端数据库中的跟踪。但是，必须指定将变更应用于服务器数据库的命令，如示例代码中所示。

API 的要点

本节提供的代码示例指出了在仅限上载同步中使用的 API 的要点。下面的代码示例指定了同步方向以及在客户端上创建表的方式。

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)

以下代码示例指定一条从服务器中检索新定位点值的命令。在本例中，将检索时间戳值并存储在客户端数据库中。在每次同步期间，定位点值用于确保上载的变更不会覆盖上次同步会话以来在服务器上发生的变更。

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

以下代码示例指定一条从服务器数据库中获取架构的命令。与其他类型的同步不同，对于仅限上载同步，此命令不从服务器数据库中获取数据。

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

下面的代码示例指定一条将来自客户端的更新应用于服务器的命令。这是一条包括了要更新的列的 UPDATE 语句。其中有一个使用了定位点值和客户端 ID 的 WHERE 子句，该定位点值是使用 SelectNewAnchorCommand 检索的。WHERE 子句还包括 @sync_force_write = 1。此参数强制应用存在冲突的更新。有关 @sync_force_write 和其他会话变量的更多信息，请参见如何使用会话变量。

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

完整的代码示例

下面的完整代码示例包括了上面介绍的代码示例以及用于执行同步的其他代码。此外，应了解如何使用 SyncStatistics 显示与同步会话有关的信息，以及如何使用 CreatingSchema 和 SchemaCreated 事件添加 CustomerId 列的默认值。示例需要 Utility 类，可通过用于数据库提供程序帮助主题的 Utility 类获得该类。

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

请参阅

概念

用于客户端与服务器同步的体系结构和类
 如何指定快照同步、下载同步、上载同步和双向同步

通过

如何将增量数据变更上载到服务器

示例

API 的要点

完整的代码示例

请参阅

概念

其他资源