Como carregar alterações de dados incrementais em um servidor
Este tópico mostra como carregar alterações de dados incrementais de um banco de dados do cliente SQL Server Compact para um banco de dados do servidor. Os exemplos deste tópico focalizam os seguintes eventos e tipos do Sync Framework:
Para obter informações sobre como executar o código de exemplo, consulte "Exemplo de aplicativos nos tópicos de instruções" em Programando tarefas comuns de sincronização do cliente e do servidor.
Exemplo
O código de exemplo neste tópico mostra como configurar a sincronização somente para upload para a tabela Customer a partir do banco de dados de amostra Sync Framework. Para obter uma visão geral das propriedades usadas para especificar a direção da sincronização, consulte Como especificar sincronização de instantâneo, de download, de carregamento e bidirecional.
A sincronização somente para upload requer que as alterações de dados incrementais sejam controladas no banco de dados do cliente e aplicadas no banco de dados do servidor. O Sync Framework cuida do controle no banco de dados do cliente. No entanto, você deve especificar os comandos que aplicam as alterações no banco de dados do servidor, como é mostrado no código de exemplo.
Partes principais da API
Esta seção fornece exemplos de código que destacam as partes principais da API usadas na sincronização somente para upload. O exemplo de código a seguir especifica a direção da sincronização e como a tabela deveria ser criada no cliente.
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)
O exemplo de código a seguir especifica um comando para recuperar um novo valor de âncora a partir do servidor. Nesse caso, um valor de carimbo de hora é recuperado e armazenado em banco de dados do cliente. Durante cada sessão de sincronização, o valor de âncora é usado para garantir que as alterações carregadas não substituam as que ocorreram no servidor desde a última sessão de sincronização.
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
O exemplo de código a seguir especifica um comando para obter o esquema a partir do banco de dados do servidor. Ao contrário dos outros tipos de sincronização, com a sincronização somente para upload, esse comando não obtém dados do banco de dados do servidor.
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
O exemplo de código a seguir especifica um comando para aplicar atualizações do cliente para o servidor. Essa é uma instrução UPDATE que inclui as colunas que queremos atualizar. Há uma cláusula WHERE que usa o valor de âncora que o SelectNewAnchorCommand recupera e a ID do cliente. A cláusula WHERE também inclui @sync_force_write = 1. Esse parâmetro faz com que atualizações conflitantes sejam aplicadas. Para obter mais informações sobre @sync_force_write e outras variáveis de sessão, consulte Como usar variáveis de sessão.
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
Exemplo de código completo
O seguinte exemplo de código completo inclui os exemplos de código descritos anteriormente e o código adicional para executar a sincronização. Além disso, saiba como o SyncStatistics é usado para exibir informações sobre a sessão de sincronização e como os eventos CreatingSchema e SchemaCreated são usados para adicionar um padrão à coluna CustomerId. O exemplo requer a classe Utility disponível em Classe de utilitário para tópicos de instruções do provedor de banco de dados.
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
Consulte também
Conceitos
Arquitetura e classes para sincronização entre cliente e servidor
Como especificar sincronização de instantâneo, de download, de carregamento e bidirecional