Procédure : télécharger un instantané des données sur un client
Cette rubrique indique comment télécharger un instantané des données à partir d'une base de données serveur vers une base de données client SQL Server Compact. Les exemples de cette rubrique reposent sur les types Sync Framework suivants :
Pour plus d'informations sur le mode d'exécution d'un exemple de code, consultez « 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 instantané des tables Customer, OrderHeader et OrderDetail 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.
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 instantané. 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.Snapshot;
customerSyncTable.SyncGroup = customerSyncGroup;
this.Configuration.SyncTables.Add(customerSyncTable);
Dim customerSyncTable As New SyncTable("Customer")
customerSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
customerSyncTable.SyncDirection = SyncDirection.Snapshot
customerSyncTable.SyncGroup = customerSyncGroup
Me.Configuration.SyncTables.Add(customerSyncTable)
L'exemple de code suivant spécifie une commande permettant de sélectionner les lignes du serveur à appliquer au client. Il s'agit d'une instruction SELECT qui inclut les colonnes à synchroniser. Vous pouvez également ajouter une clause WHERE pour filtrer les lignes. Pour plus d'informations sur le filtrage, consultez Procédure : filtrer des lignes et des colonnes. Du fait que les données sont intégralement actualisées lors de chaque synchronisation, la commande n'inclut pas les colonnes de suivi qui sont nécessaires pour la synchronisation par téléchargement uniquement et bidirectionnelle.
SyncAdapter customerSyncAdapter = new SyncAdapter("Customer");
SqlCommand customerIncrInserts = new SqlCommand();
customerIncrInserts.CommandText =
"SELECT CustomerId, CustomerName, SalesPerson, CustomerType " +
"FROM Sales.Customer";
customerIncrInserts.Connection = serverConn;
customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts;
this.SyncAdapters.Add(customerSyncAdapter);
Dim customerSyncAdapter As New SyncAdapter("Customer")
Dim customerIncrInserts As New SqlCommand()
customerIncrInserts.CommandText = _
"SELECT CustomerId, CustomerName, SalesPerson, CustomerType " _
& "FROM Sales.Customer"
customerIncrInserts.Connection = serverConn
customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts
Me.SyncAdapters.Add(customerSyncAdapter)
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. 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 server.
Utility.MakeDataChangesOnServer("Customer");
//Subsequent synchronization. There was one insert,
//one update, and one delete made on the server;
//therefore, the row count is identical, but the
//data is different.
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 two SyncGroups so that changes to OrderHeader
//and OrderDetail are made in one transaction. Depending on
//application requirements, you might include Customer
//in the same group.
SyncGroup customerSyncGroup = new SyncGroup("Customer");
SyncGroup orderSyncGroup = new SyncGroup("Order");
//Add each table: specify a synchronization direction of
//Snapshot, and that any existing tables should be dropped.
SyncTable customerSyncTable = new SyncTable("Customer");
customerSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
customerSyncTable.SyncDirection = SyncDirection.Snapshot;
customerSyncTable.SyncGroup = customerSyncGroup;
this.Configuration.SyncTables.Add(customerSyncTable);
SyncTable orderHeaderSyncTable = new SyncTable("OrderHeader");
orderHeaderSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
orderHeaderSyncTable.SyncDirection = SyncDirection.Snapshot;
orderHeaderSyncTable.SyncGroup = orderSyncGroup;
this.Configuration.SyncTables.Add(orderHeaderSyncTable);
SyncTable orderDetailSyncTable = new SyncTable("OrderDetail");
orderDetailSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
orderDetailSyncTable.SyncDirection = SyncDirection.Snapshot;
orderDetailSyncTable.SyncGroup = orderSyncGroup;
this.Configuration.SyncTables.Add(orderDetailSyncTable);
}
}
//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 SyncAdapter for each table, and then define
//the command to select rows from the table. With the Snapshot
//option, you do not download incremental changes. However,
//you still use the SelectIncrementalInsertsCommand to select
//the rows to download for each snapshot. The commands include
//only those columns that you want on the client.
//Customer table.
SyncAdapter customerSyncAdapter = new SyncAdapter("Customer");
SqlCommand customerIncrInserts = new SqlCommand();
customerIncrInserts.CommandText =
"SELECT CustomerId, CustomerName, SalesPerson, CustomerType " +
"FROM Sales.Customer";
customerIncrInserts.Connection = serverConn;
customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts;
this.SyncAdapters.Add(customerSyncAdapter);
//OrderHeader table.
SyncAdapter orderHeaderSyncAdapter = new SyncAdapter("OrderHeader");
SqlCommand orderHeaderIncrInserts = new SqlCommand();
orderHeaderIncrInserts.CommandText =
"SELECT OrderId, CustomerId, OrderDate, OrderStatus " +
"FROM Sales.OrderHeader";
orderHeaderIncrInserts.Connection = serverConn;
orderHeaderSyncAdapter.SelectIncrementalInsertsCommand = orderHeaderIncrInserts;
this.SyncAdapters.Add(orderHeaderSyncAdapter);
//OrderDetail table.
SyncAdapter orderDetailSyncAdapter = new SyncAdapter("OrderDetail");
SqlCommand orderDetailIncrInserts = new SqlCommand();
orderDetailIncrInserts.CommandText =
"SELECT OrderDetailId, OrderId, Product, Quantity " +
"FROM Sales.OrderDetail";
orderDetailIncrInserts.Connection = serverConn;
orderDetailSyncAdapter.SelectIncrementalInsertsCommand = orderDetailIncrInserts;
this.SyncAdapters.Add(orderDetailSyncAdapter);
}
}
//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 you could use this class to handle client
//provider events and other client-side processing.
public class SampleClientSyncProvider : SqlCeClientSyncProvider
{
public SampleClientSyncProvider()
{
//Specify a connection string for the sample client database.
Utility util = new Utility();
this.ConnectionString = Utility.ConnStr_SqlCeClientSync;
}
}
//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 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 server.
Utility.MakeDataChangesOnServer("Customer")
'Subsequent synchronization. There was one insert,
'one update, and one delete made on the server;
'therefore, the row count is identical, but the
'data is different.
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 two SyncGroups so that changes to OrderHeader
'and OrderDetail are made in one transaction. Depending on
'application requirements, you might include Customer
'in the same group.
Dim customerSyncGroup As New SyncGroup("Customer")
Dim orderSyncGroup As New SyncGroup("Order")
'Add each table: specify a synchronization direction of
'Snapshot, and that any existing tables should be dropped.
Dim customerSyncTable As New SyncTable("Customer")
customerSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
customerSyncTable.SyncDirection = SyncDirection.Snapshot
customerSyncTable.SyncGroup = customerSyncGroup
Me.Configuration.SyncTables.Add(customerSyncTable)
Dim orderHeaderSyncTable As New SyncTable("OrderHeader")
orderHeaderSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
orderHeaderSyncTable.SyncDirection = SyncDirection.Snapshot
orderHeaderSyncTable.SyncGroup = orderSyncGroup
Me.Configuration.SyncTables.Add(orderHeaderSyncTable)
Dim orderDetailSyncTable As New SyncTable("OrderDetail")
orderDetailSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
orderDetailSyncTable.SyncDirection = SyncDirection.Snapshot
orderDetailSyncTable.SyncGroup = orderSyncGroup
Me.Configuration.SyncTables.Add(orderDetailSyncTable)
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 SyncAdapter for each table, and then define
'the command to select rows from the table. With the Snapshot
'option, you do not download incremental changes. However,
'you still use the SelectIncrementalInsertsCommand to select
'the rows to download for each snapshot. The commands include
'only those columns that you want on the client.
'Customer table.
Dim customerSyncAdapter As New SyncAdapter("Customer")
Dim customerIncrInserts As New SqlCommand()
customerIncrInserts.CommandText = _
"SELECT CustomerId, CustomerName, SalesPerson, CustomerType " _
& "FROM Sales.Customer"
customerIncrInserts.Connection = serverConn
customerSyncAdapter.SelectIncrementalInsertsCommand = customerIncrInserts
Me.SyncAdapters.Add(customerSyncAdapter)
'OrderHeader table.
Dim orderHeaderSyncAdapter As New SyncAdapter("OrderHeader")
Dim orderHeaderIncrInserts As New SqlCommand()
orderHeaderIncrInserts.CommandText = _
"SELECT OrderId, CustomerId, OrderDate, OrderStatus " _
& "FROM Sales.OrderHeader"
orderHeaderIncrInserts.Connection = serverConn
orderHeaderSyncAdapter.SelectIncrementalInsertsCommand = orderHeaderIncrInserts
Me.SyncAdapters.Add(orderHeaderSyncAdapter)
'OrderDetail table.
Dim orderDetailSyncAdapter As New SyncAdapter("OrderDetail")
Dim orderDetailIncrInserts As New SqlCommand()
orderDetailIncrInserts.CommandText = _
"SELECT OrderDetailId, OrderId, Product, Quantity " _
& "FROM Sales.OrderDetail"
orderDetailIncrInserts.Connection = serverConn
orderDetailSyncAdapter.SelectIncrementalInsertsCommand = orderDetailIncrInserts
Me.SyncAdapters.Add(orderDetailSyncAdapter)
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 you could use this class to handle client
'provider events and other client-side processing.
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
End Sub 'New
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 Downloaded: " & syncStatistics.TotalChangesDownloaded)
Console.WriteLine("Complete Time: " & syncStatistics.SyncCompleteTime)
Console.WriteLine(String.Empty)
End Sub 'DisplayStats
End Class 'SampleStats
Voir aussi
Concepts
Architecture et classes pour la synchronisation client et serveur
Procédure : spécifier la synchronisation par instantané, par téléchargement, par téléchargement ascendant et bidirectionnelle