Inicializar la base de datos cliente y trabajar con el esquema de tablas

Artículo
10/17/2009

En este tema se describe cómo se inicializa una base de datos cliente de SQL Server Compact y se trabaja con el esquema de dicha base de datos. Los ejemplos de este tema se centran en los tipos y eventos siguientes de Sync Framework:

Para obtener información acerca de cómo ejecutar código de ejemplo, vea "Aplicaciones de ejemplo en los temas sobre procedimientos en Programar tareas comunes de sincronización de cliente y servidor.

Introducción a la inicialización

Para inicializar la base de datos del cliente normalmente se necesita copiar el esquema de usuario y los datos en la base de datos, así como habilitar el seguimiento de cambios en la base de datos (el seguimiento de cambios no está habilitado para la sincronización de instantáneas). Para obtener más información, vea Arquitectura y clases para la sincronización del cliente y el servidor. De forma predeterminada, el proveedor de sincronización del cliente copia los datos y el esquema de usuario desde la base de datos del servidor y después los aplica a la base de datos del cliente. Incluso en los escenarios de sólo carga, de forma predeterminada el esquema se crea en el cliente. También puede crear manualmente la base de datos del cliente, y especificar que las tablas de la base de datos se conserven mientras tiene lugar la sincronización.

De forma predeterminada, las restricciones siguientes no se copian al cliente: FOREIGN KEY, UNIQUE y DEFAULT. Como se muestra en el ejemplo, puede agregar estas restricciones si la aplicación las requiere. Asimismo, algunos tipos de columnas tienen un tratamiento distinto en el cliente y en el servidor. Para obtener más información, vea Consideraciones y asignación de tipos de datos.

Después de inicializar el esquema en la base de datos del cliente, se descargan los datos iniciales de las tablas que participan en una sincronización de instantáneas, de sólo descarga y bidireccional, por medio de la consulta que se especifica para la propiedad SelectIncrementalInsertsCommand. La base de datos del cliente también recibe un Id. de cliente. Este Id. es un GUID que se expone por medio de la propiedad ClientId, que identifica de forma inequívoca al cliente ante el servidor. Después de crear la base de datos del cliente, como parte de la implementación puede empaquetar una copia de la base de datos que contenga la aplicación. El Id. de cliente se regenera en cada cliente durante la primera sincronización.

Ejemplo

De forma predeterminada, la inicialización de la base de datos del cliente no requiere un código adicional. Para obtener un ejemplo, vea el código de Descargar una instantánea de datos a un cliente. No obstante, la API proporciona un alto grado de flexibilidad. El ejemplo siguiente ofrece una demostración de cuatro métodos de inicialización del esquema de tablas y para trabajar con él en la base de datos del cliente:

La tabla Customer se inicializa mediante la llamada a un método en la clase Utility. Este método crea el esquema en el cliente mediante el uso de SQL. La clase Utility está disponible en Clase de utilidad para los temas de procedimientos del proveedor de bases de datos. Se agrega a la tabla una columna SalesNotes que no está presente en el servidor. Esta columna puede utilizarse en el cliente, pero los datos no se sincronizan. Cuando se define una SyncTable para la tabla Customer, se especifica un valor de UseExistingTableOrFail para la propiedad CreationOption. Esto permite asegurar que la tabla no se sobrescriba durante la primera sincronización.
La tabla CustomerContact se inicializa de forma predeterminada. Para esta tabla y las dos próximas, se especifica un valor de DropExistingOrCreateNewTable.
La tabla OrderHeader se inicializa pasando un conjunto de datos al constructor SyncSchema. El conjunto de datos se crea mediante una llamada a un método de la clase Utility.
Se inicializa la tabla OrderDetail agregando la tabla y sus columnas al objeto SyncSchema creado mediante el uso del conjunto de datos OrderHeader. Como se muestra en el código, el control sobre la creación del esquema en el cliente es muy preciso. Sync Framework permite especificar la gama completa de propiedades relacionadas con esquemas expuestas por ADO.NET.

El código también muestra dos eventos SqlCeClientSyncProvider asociados a la creación de esquemas:

CreatingSchema. Este evento se genera antes de la creación del esquema. Este evento se utiliza para cambiar el esquema mediante el uso de la API.
SchemaCreated. Este evento se genera después de la creación del esquema. Este evento se utiliza para cambiar el esquema mediante el uso de SQL.

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);

            //Create the Customer table on the client by using SQL. We add
            //a SalesNotes column that will not be synchronized.
            //When we create the Customer SyncTable, we specify that
            //Sync Framework should use an existing table.          
            Utility.CreateTableOnClient();

            //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 and client.
            Utility.MakeDataChangesOnServer("Customer");
            Utility.MakeDataChangesOnClient("Customer");

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

            //Return the 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
            //and CustomerContact in the same group.
            SyncGroup customerSyncGroup = new SyncGroup("Customer");
            SyncGroup orderSyncGroup = new SyncGroup("Order");

            //Add each table: specify a synchronization direction of
            //Bidirectional. We create the Customer table before sync:
            //we set CreationOption to UseExistingTableOrFail so
            //we are sure that the table exists.
            SyncTable customerSyncTable = new SyncTable("Customer");
            customerSyncTable.CreationOption = TableCreationOption.UseExistingTableOrFail;
            customerSyncTable.SyncDirection = SyncDirection.Bidirectional;
            customerSyncTable.SyncGroup = customerSyncGroup;
            this.Configuration.SyncTables.Add(customerSyncTable);

            SyncTable customerContactSyncTable = new SyncTable("CustomerContact");
            customerContactSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
            customerContactSyncTable.SyncDirection = SyncDirection.Bidirectional;
            customerContactSyncTable.SyncGroup = customerSyncGroup;
            this.Configuration.SyncTables.Add(customerContactSyncTable);

            SyncTable orderHeaderSyncTable = new SyncTable("OrderHeader");
            orderHeaderSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
            orderHeaderSyncTable.SyncDirection = SyncDirection.Bidirectional;
            orderHeaderSyncTable.SyncGroup = orderSyncGroup;
            this.Configuration.SyncTables.Add(orderHeaderSyncTable);            

            SyncTable orderDetailSyncTable = new SyncTable("OrderDetail");
            orderDetailSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
            orderDetailSyncTable.SyncDirection = SyncDirection.Bidirectional;
            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 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 SyncAdapters for each table by using the SqlSyncAdapterBuilder:
            //  * Specify the base table and tombstone table names.
            //  * Specify the columns that are used to track when
            //    and where changes are made.
            //  * Specify bidirectional synchronization, so that all
            //    commands are generated.
            //  * Call ToSyncAdapter to create the SyncAdapter.
            //  * Specify a name for the SyncAdapter that matches the
            //    the name specified for the corresponding SyncTable.
            //    Do not include the schema names (Sales in this case).
                        
            //Customer table
            SqlSyncAdapterBuilder customerBuilder = new SqlSyncAdapterBuilder(serverConn);
            
            customerBuilder.TableName = "Sales.Customer";
            customerBuilder.TombstoneTableName = customerBuilder.TableName + "_Tombstone";
            customerBuilder.SyncDirection = SyncDirection.Bidirectional;
            customerBuilder.CreationTrackingColumn = "InsertTimestamp";
            customerBuilder.UpdateTrackingColumn = "UpdateTimestamp";
            customerBuilder.DeletionTrackingColumn = "DeleteTimestamp";
            customerBuilder.CreationOriginatorIdColumn = "InsertId";
            customerBuilder.UpdateOriginatorIdColumn = "UpdateId";
            customerBuilder.DeletionOriginatorIdColumn = "DeleteId";

            SyncAdapter customerSyncAdapter = customerBuilder.ToSyncAdapter();
            customerSyncAdapter.TableName = "Customer";
            this.SyncAdapters.Add(customerSyncAdapter);


            //CustomerContact table.
            SqlSyncAdapterBuilder customerContactBuilder = new SqlSyncAdapterBuilder(serverConn);

            customerContactBuilder.TableName = "Sales.CustomerContact";
            customerContactBuilder.TombstoneTableName = customerContactBuilder.TableName + "_Tombstone";
            customerContactBuilder.SyncDirection = SyncDirection.Bidirectional;
            customerContactBuilder.CreationTrackingColumn = "InsertTimestamp";
            customerContactBuilder.UpdateTrackingColumn = "UpdateTimestamp";
            customerContactBuilder.DeletionTrackingColumn = "DeleteTimestamp";
            customerContactBuilder.CreationOriginatorIdColumn = "InsertId";
            customerContactBuilder.UpdateOriginatorIdColumn = "UpdateId";
            customerContactBuilder.DeletionOriginatorIdColumn = "DeleteId";
            
            SyncAdapter customerContactSyncAdapter = customerContactBuilder.ToSyncAdapter();
            customerContactSyncAdapter.TableName = "CustomerContact";
            this.SyncAdapters.Add(customerContactSyncAdapter);


            //OrderHeader table.
            SqlSyncAdapterBuilder orderHeaderBuilder = new SqlSyncAdapterBuilder(serverConn);

            orderHeaderBuilder.TableName = "Sales.OrderHeader";
            orderHeaderBuilder.TombstoneTableName = orderHeaderBuilder.TableName + "_Tombstone";
            orderHeaderBuilder.SyncDirection = SyncDirection.Bidirectional;
            orderHeaderBuilder.CreationTrackingColumn = "InsertTimestamp";
            orderHeaderBuilder.UpdateTrackingColumn = "UpdateTimestamp";
            orderHeaderBuilder.DeletionTrackingColumn = "DeleteTimestamp";
            orderHeaderBuilder.CreationOriginatorIdColumn = "InsertId";
            orderHeaderBuilder.UpdateOriginatorIdColumn = "UpdateId";
            orderHeaderBuilder.DeletionOriginatorIdColumn = "DeleteId";

            SyncAdapter orderHeaderSyncAdapter = orderHeaderBuilder.ToSyncAdapter();
            orderHeaderSyncAdapter.TableName = "OrderHeader";
            this.SyncAdapters.Add(orderHeaderSyncAdapter);


            //OrderDetail table.
            SqlSyncAdapterBuilder orderDetailBuilder = new SqlSyncAdapterBuilder(serverConn);

            orderDetailBuilder.TableName = "Sales.OrderDetail";
            orderDetailBuilder.TombstoneTableName = orderDetailBuilder.TableName + "_Tombstone";
            orderDetailBuilder.SyncDirection = SyncDirection.Bidirectional;
            orderDetailBuilder.CreationTrackingColumn = "InsertTimestamp";
            orderDetailBuilder.UpdateTrackingColumn = "UpdateTimestamp";
            orderDetailBuilder.DeletionTrackingColumn = "DeleteTimestamp";
            orderDetailBuilder.CreationOriginatorIdColumn = "InsertId";
            orderDetailBuilder.UpdateOriginatorIdColumn = "UpdateId";
            orderDetailBuilder.DeletionOriginatorIdColumn = "DeleteId";

            SyncAdapter orderDetailSyncAdapter = orderDetailBuilder.ToSyncAdapter();
            orderDetailSyncAdapter.TableName = "OrderDetail";
            this.SyncAdapters.Add(orderDetailSyncAdapter);

            //Create the schema for the OrderHeader and OrderDetail tables.
            //We first create a schema based on a DataSet that contains only
            //the OrderHeader table. As with the SyncAdapter, the table name
            //must match the SyncTable name. We then add the schema for the 
            //OrderDetail table; this is the place to map data types if
            //your application requires it.
            DataSet orderHeaderDataSet = Utility.CreateDataSetFromServer();
            orderHeaderDataSet.Tables[0].TableName = "OrderHeader";
            this.Schema = new SyncSchema(orderHeaderDataSet);
            
            this.Schema.Tables.Add("OrderDetail");

            this.Schema.Tables["OrderDetail"].Columns.Add("OrderDetailId");
            this.Schema.Tables["OrderDetail"].Columns["OrderDetailId"].ProviderDataType = "int";
            this.Schema.Tables["OrderDetail"].Columns["OrderDetailId"].AllowNull = false;

            this.Schema.Tables["OrderDetail"].Columns.Add("OrderId");
            this.Schema.Tables["OrderDetail"].Columns["OrderId"].ProviderDataType = "uniqueidentifier";
            this.Schema.Tables["OrderDetail"].Columns["OrderId"].RowGuid = true;
            this.Schema.Tables["OrderDetail"].Columns["OrderId"].AllowNull = false;

            this.Schema.Tables["OrderDetail"].Columns.Add("Product");
            this.Schema.Tables["OrderDetail"].Columns["Product"].ProviderDataType = "nvarchar";
            this.Schema.Tables["OrderDetail"].Columns["Product"].MaxLength = 100;
            this.Schema.Tables["OrderDetail"].Columns["Product"].AllowNull = false;

            this.Schema.Tables["OrderDetail"].Columns.Add("Quantity");
            this.Schema.Tables["OrderDetail"].Columns["Quantity"].ProviderDataType = "int";
            this.Schema.Tables["OrderDetail"].Columns["Quantity"].AllowNull = false;
           
            //The primary key columns are passed as a string array.
            string[] orderDetailPrimaryKey = new string[2];
            orderDetailPrimaryKey[0] = "OrderDetailId";
            orderDetailPrimaryKey[1] = "OrderId";
            this.Schema.Tables["OrderDetail"].PrimaryKey = orderDetailPrimaryKey;
        }
    }

    //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.
            //Note that both schema events fire for the Customer table,
            //even though we already created the table. This allows us
            //to work with the table at this point if we need to.
            this.CreatingSchema += new EventHandler<CreatingSchemaEventArgs>(SampleClientSyncProvider_CreatingSchema);
            this.SchemaCreated += new EventHandler<SchemaCreatedEventArgs>(SampleClientSyncProvider_SchemaCreated);
        }

        private void SampleClientSyncProvider_CreatingSchema(object sender, CreatingSchemaEventArgs e)
        {
            
            string tableName = e.Table.TableName;
            
            Console.Write("Creating schema for " + tableName + " | ");
            
            if (tableName == "OrderHeader")
            {
                //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.
                e.Schema.Tables["OrderHeader"].Columns["OrderId"].RowGuid = true;
                
            }

            if (tableName == "OrderDetail")
            {
                //Add a foreign key between the OrderDetail and OrderHeader tables.
                e.Schema.Tables["OrderDetail"].ForeignKeys.Add("FK_OrderDetail_OrderHeader", "OrderHeader", "OrderId", "OrderDetail", "OrderId");
            }
        }

        private void SampleClientSyncProvider_SchemaCreated(object sender, SchemaCreatedEventArgs e)
        {
            string tableName = e.Table.TableName; 
            Utility util = new Utility();

            //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.
            if (tableName == "OrderHeader")
            {
                Utility.MakeSchemaChangesOnClient(e.Connection, e.Transaction, "OrderHeader");                
            }

            if (tableName == "OrderDetail")
            {
                Utility.MakeSchemaChangesOnClient(e.Connection, e.Transaction, "OrderDetail");                
            }

            Console.WriteLine("Schema created for " + 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)

        'Create the Customer table on the client by using SQL. We add
        'a SalesNotes column that will not be synchronized.
        'When we create the Customer SyncTable, we specify that
        'Sync Framework should use an existing table.          
        Utility.CreateTableOnClient()

        '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 and client.
        Utility.MakeDataChangesOnServer("Customer")
        Utility.MakeDataChangesOnClient("Customer")

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

        'Return the 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
        'and CustomerContact in the same group.
        Dim customerSyncGroup As New SyncGroup("Customer")
        Dim orderSyncGroup As New SyncGroup("Order")

        'Add each table: specify a synchronization direction of
        'Bidirectional. We create the Customer table before sync:
        'we set CreationOption to UseExistingTableOrFail so
        'we are sure that the table exists.
        Dim customerSyncTable As New SyncTable("Customer")
        customerSyncTable.CreationOption = TableCreationOption.UseExistingTableOrFail
        customerSyncTable.SyncDirection = SyncDirection.Bidirectional
        customerSyncTable.SyncGroup = customerSyncGroup
        Me.Configuration.SyncTables.Add(customerSyncTable)

        Dim customerContactSyncTable As New SyncTable("CustomerContact")
        customerContactSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
        customerContactSyncTable.SyncDirection = SyncDirection.Bidirectional
        customerContactSyncTable.SyncGroup = customerSyncGroup
        Me.Configuration.SyncTables.Add(customerContactSyncTable)

        Dim orderHeaderSyncTable As New SyncTable("OrderHeader")
        orderHeaderSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
        orderHeaderSyncTable.SyncDirection = SyncDirection.Bidirectional
        orderHeaderSyncTable.SyncGroup = orderSyncGroup
        Me.Configuration.SyncTables.Add(orderHeaderSyncTable)

        Dim orderDetailSyncTable As New SyncTable("OrderDetail")
        orderDetailSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable
        orderDetailSyncTable.SyncDirection = SyncDirection.Bidirectional
        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 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 SyncAdapters for each table by using the SqlSyncAdapterBuilder:
        '  * Specify the base table and tombstone table names.
        '  * Specify the columns that are used to track when
        '    and where changes are made.
        '  * Specify bidirectional synchronization, so that all
        '    commands are generated.
        '  * Call ToSyncAdapter to create the SyncAdapter.
        '  * Specify a name for the SyncAdapter that matches the
        '    the name specified for the corresponding SyncTable.
        '    Do not include the schema names (Sales in this case).
        'Customer table
        Dim customerBuilder As New SqlSyncAdapterBuilder(serverConn)

        With customerBuilder
            .TableName = "Sales.Customer"
            .TombstoneTableName = customerBuilder.TableName + "_Tombstone"
            .SyncDirection = SyncDirection.Bidirectional
            .CreationTrackingColumn = "InsertTimestamp"
            .UpdateTrackingColumn = "UpdateTimestamp"
            .DeletionTrackingColumn = "DeleteTimestamp"
            .CreationOriginatorIdColumn = "InsertId"
            .UpdateOriginatorIdColumn = "UpdateId"
            .DeletionOriginatorIdColumn = "DeleteId"
        End With

        Dim customerSyncAdapter As SyncAdapter = customerBuilder.ToSyncAdapter()
        customerSyncAdapter.TableName = "Customer"
        Me.SyncAdapters.Add(customerSyncAdapter)


        'CustomerContact table.
        Dim customerContactBuilder As New SqlSyncAdapterBuilder(serverConn)

        With customerContactBuilder
            .TableName = "Sales.CustomerContact"
            .TombstoneTableName = customerContactBuilder.TableName + "_Tombstone"
            .SyncDirection = SyncDirection.Bidirectional
            .CreationTrackingColumn = "InsertTimestamp"
            .UpdateTrackingColumn = "UpdateTimestamp"
            .DeletionTrackingColumn = "DeleteTimestamp"
            .CreationOriginatorIdColumn = "InsertId"
            .UpdateOriginatorIdColumn = "UpdateId"
            .DeletionOriginatorIdColumn = "DeleteId"
        End With

        Dim customerContactSyncAdapter As SyncAdapter = customerContactBuilder.ToSyncAdapter()
        customerContactSyncAdapter.TableName = "CustomerContact"
        Me.SyncAdapters.Add(customerContactSyncAdapter)


        'OrderHeader table.
        Dim orderHeaderBuilder As New SqlSyncAdapterBuilder(serverConn)

        With orderHeaderBuilder
            .TableName = "Sales.OrderHeader"
            .TombstoneTableName = orderHeaderBuilder.TableName + "_Tombstone"
            .SyncDirection = SyncDirection.Bidirectional
            .CreationTrackingColumn = "InsertTimestamp"
            .UpdateTrackingColumn = "UpdateTimestamp"
            .DeletionTrackingColumn = "DeleteTimestamp"
            .CreationOriginatorIdColumn = "InsertId"
            .UpdateOriginatorIdColumn = "UpdateId"
            .DeletionOriginatorIdColumn = "DeleteId"
        End With

        Dim orderHeaderSyncAdapter As SyncAdapter = orderHeaderBuilder.ToSyncAdapter()
        orderHeaderSyncAdapter.TableName = "OrderHeader"
        Me.SyncAdapters.Add(orderHeaderSyncAdapter)


        'OrderDetail table.
        Dim orderDetailBuilder As New SqlSyncAdapterBuilder(serverConn)

        With orderDetailBuilder
            .TableName = "Sales.OrderDetail"
            .TombstoneTableName = orderDetailBuilder.TableName + "_Tombstone"
            .SyncDirection = SyncDirection.Bidirectional
            .CreationTrackingColumn = "InsertTimestamp"
            .UpdateTrackingColumn = "UpdateTimestamp"
            .DeletionTrackingColumn = "DeleteTimestamp"
            .CreationOriginatorIdColumn = "InsertId"
            .UpdateOriginatorIdColumn = "UpdateId"
            .DeletionOriginatorIdColumn = "DeleteId"
        End With

        Dim orderDetailSyncAdapter As SyncAdapter = orderDetailBuilder.ToSyncAdapter()
        orderDetailSyncAdapter.TableName = "OrderDetail"
        Me.SyncAdapters.Add(orderDetailSyncAdapter)

        'Create the schema for the OrderHeader and OrderDetail tables.
        'We first create a schema based on a DataSet that contains only
        'the OrderHeader table. As with the SyncAdapter, the table name
        'must match the SyncTable name. We then add the schema for the 
        'OrderDetail table; this is the place to map data types if
        'your application requires it.
        Dim orderHeaderDataSet As DataSet = Utility.CreateDataSetFromServer()
        orderHeaderDataSet.Tables(0).TableName = "OrderHeader"
        Me.Schema = New SyncSchema(orderHeaderDataSet)

        With Me.Schema
            .Tables.Add("OrderDetail")

            .Tables("OrderDetail").Columns.Add("OrderDetailId")
            .Tables("OrderDetail").Columns("OrderDetailId").ProviderDataType = "int"
            .Tables("OrderDetail").Columns("OrderDetailId").AllowNull = False

            .Tables("OrderDetail").Columns.Add("OrderId")
            .Tables("OrderDetail").Columns("OrderId").ProviderDataType = "uniqueidentifier"
            .Tables("OrderDetail").Columns("OrderId").RowGuid = True
            .Tables("OrderDetail").Columns("OrderId").AllowNull = False

            .Tables("OrderDetail").Columns.Add("Product")
            .Tables("OrderDetail").Columns("Product").ProviderDataType = "nvarchar"
            .Tables("OrderDetail").Columns("Product").MaxLength = 100
            .Tables("OrderDetail").Columns("Product").AllowNull = False

            .Tables("OrderDetail").Columns.Add("Quantity")
            .Tables("OrderDetail").Columns("Quantity").ProviderDataType = "int"
            .Tables("OrderDetail").Columns("Quantity").AllowNull = False
        End With        

        'The primary key columns are passed as a string array.
        Dim orderDetailPrimaryKey(1) As String
        orderDetailPrimaryKey(0) = "OrderDetailId"
        orderDetailPrimaryKey(1) = "OrderId"
        Me.Schema.Tables("OrderDetail").PrimaryKey = orderDetailPrimaryKey

    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.
        'Note that both schema events fire for the Customer table,
        'even though we already created the table. This allows us
        'to work with the table at this point if we need to.
        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)

        Dim tableName As String = e.Table.TableName

        Console.Write("Creating schema for " + tableName + " | ")

        If tableName = "OrderHeader" Then
            '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.
            e.Schema.Tables("OrderHeader").Columns("OrderId").RowGuid = True
        End If

        If tableName = "OrderDetail" Then
            'Add a foreign key  between the OrderHeader and OrderDetail tables.
            e.Schema.Tables("OrderDetail").ForeignKeys.Add("FK_OrderDetail_OrderHeader", "OrderHeader", "OrderId", "OrderDetail", "OrderId")
        End If


    End Sub 'SampleClientSyncProvider_CreatingSchema


    Private Sub SampleClientSyncProvider_SchemaCreated(ByVal sender As Object, ByVal e As SchemaCreatedEventArgs)
        Dim tableName As String = e.Table.TableName
        Dim util As New Utility()

        '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.
        If tableName = "OrderHeader" Then
            Utility.MakeSchemaChangesOnClient(e.Connection, e.Transaction, "OrderHeader")
        End If

        If tableName = "OrderDetail" Then
            Utility.MakeSchemaChangesOnClient(e.Connection, e.Transaction, "OrderDetail")            
        End If

        Console.WriteLine("Schema created for " + 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

Vea también

Conceptos

Programar tareas comunes de sincronización de cliente y servidor

Compartir a través de

Inicializar la base de datos cliente y trabajar con el esquema de tablas

Introducción a la inicialización

Ejemplo

Vea también

Conceptos

Recursos adicionales