セッション変数を使用する方法

このトピックでは、Sync Framework でセッション変数を使用する方法について説明します。このトピックの例では、次に示す Sync Framework の型を中心に説明します。

サンプル コードを実行する方法については、「一般的なクライアントとサーバーの同期タスクのプログラミング」の「操作方法に関するトピックのサンプル アプリケーション」を参照してください。

セッション変数について

Sync Framework には、一連のセッション変数が用意されており、これらを使用すると、同期中に SyncAdapter コマンドと DbServerSyncProvider コマンドに値を渡すことができます。これらの変数は、ADO.NET コマンドのクエリやストアド プロシージャに対する他のパラメーターと同じように指定します。同期セッション中、DbServerSyncProvider は、各 ADO.NET のコマンド オブジェクトを呼び出すとき、同期パラメーターのコレクション (SyncParameters) を走査することによって、各パラメーターを名前に基づいて ADO.NET のコマンド パラメーターに対応付けることができるかどうかを判断します。組み込みセッション変数、または独自に定義したパラメーターが見つかった場合は、Sync Framework によってその変数に値が設定され、その後で、プロバイダーがコマンドを呼び出します。

たとえば、次のクエリでは、sync_last_received_anchorsync_new_received_anchor、および sync_client_id の各セッション変数を使用して、Customer テーブルから変更を選択します。

"SELECT CustomerId, CustomerName, SalesPerson, CustomerType FROM
Sales.Customer WHERE InsertTimestamp > @sync_last_received_anchor AND
InsertTimestamp <= @sync_new_received_anchor AND InsertId <>
@sync_client_id"

これらの変数の値は、同期中に Sync Framework によって指定されます。上記のクエリのように変数名を直接使用することも、SyncSession オブジェクトから取得した定数を使用することができます。

"SELECT CustomerId, CustomerName, SalesPerson, CustomerType FROM
Sales.Customer WHERE InsertTimestamp > @" +
SyncSession.SyncLastReceivedAnchor + 
" AND InsertTimestamp <= @" +
SyncSession.SyncNewReceivedAnchor +
" AND InsertId <> @"
SyncSession.SyncClientId

次の表に、使用可能なすべてのセッション変数とその使用方法を示します。

セッション変数 使用方法

sync_client_idsync_client_id_hashsync_client_id_binary、および sync_originator_id

現在同期中のクライアントを識別するために使用します。ID は、通常、競合検出や、双方向同期中に変更がクライアントにエコー バックされないようにするために使用します。詳細については、「クライアントとサーバー間で双方向でデータの増分変更を交換する方法」を参照してください。

既定では、Sync Framework は sync_client_id から返された GUID で各クライアントを識別します。また、ID のハッシュを作成してクエリ内で sync_client_id_hash を使用することもできます。sync_client_id_binary は、SQL Server の変更追跡機能を使用して変更を追跡する場合に便利です。さらに、GUID を sync_client_id から整数にマップして sync_originator_id を使用することもできます。詳細については、この後の「例」を参照してください。

sync_last_received_anchor およびsync_new_received_anchor

セッション中に同期される一連の変更を定義するために使用します。現在の同期中に、SelectNewAnchorCommand プロパティに指定されたコマンドによって、新しいアンカー値が提供されます。最後にアンカー値を受け取ったときから、新しいアンカー値を受け取る前までに加えられた変更が同期されます。その後、新しく受け取ったアンカーが格納され、次の同期時に最後に受け取ったアンカー値として使用されます。詳細については、「サーバー データベースの変更の追跡」の「クライアントにダウンロードするデータ変更を決める」を参照してください。

sync_force_write

RetryWithForceWriteApplyAction で使用して、競合またはエラーが原因で失敗した変更を強制的に適用します。詳細については、「データの競合とエラーを処理する方法」を参照してください。

sync_row_count

サーバーで実行された最後の操作で処理された行数を返します。SQL Server データベースでは、@@ROWCOUNT によって、この変数に値が指定されます。行数 0 は、操作が失敗したことを示します。一般的な原因としては、競合またはエラーが挙げられます。詳細については、「データの競合とエラーを処理する方法」を参照してください。

sync_initialized

現在の同期が最初の同期 (値 0) かその後の同期 (値 1) かを返します。

sync_table_namesync_group_name

クエリでテーブル名またはグループ名を指定する必要がある場合に使用します。

sync_batch_countsync_batch_sizesync_max_received_anchor

変更をバッチ処理する場合に使用します。詳細については、「変更の順序とバッチ サイズを指定する方法」を参照してください。

sync_session_id

現在の同期セッションを識別する GUID 値を返します。

次のコード例は、Sync Framework サンプル データベースの Vendor テーブルの同期中にセッション変数を使用する方法を示しています。

API の主要部分

このセクションでは、セッション変数に関連する API の主要部分に注目したコード例を示します。次のコード例では、SelectNewAnchorCommand プロパティにクエリを指定します。これにより、sync_new_received_anchor 変数の値が設定されます。この値は、サーバー データベースから変更を選択する同期コマンドで使用されます。

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

次のコード例では、サーバーから増分更新を選択してクライアントに適用するコマンドを指定します。このコマンドには、アンカー変数と sync_originator_id 変数が含まれています。sync_originator_id 変数の値は、SelectClientIdCommand プロパティに指定されたクエリによって指定されます。このクエリとプロパティについては、このセクションの最後で説明します。

SqlCommand vendorIncrUpdates = new SqlCommand();
vendorIncrUpdates.CommandText =
    "SELECT VendorId, VendorName, CreditRating, PreferredVendor " +
    "FROM Sales.Vendor " +
    "WHERE (UpdateTimestamp > @sync_last_received_anchor " +
    "AND UpdateTimestamp <= @sync_new_received_anchor " +
    "AND UpdateId <> @sync_originator_id " +
    "AND NOT (InsertTimestamp > @sync_last_received_anchor " +
    "AND InsertId <> @sync_originator_id))";
vendorIncrUpdates.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
vendorIncrUpdates.Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp);
vendorIncrUpdates.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
vendorIncrUpdates.Connection = serverConn;
vendorSyncAdapter.SelectIncrementalUpdatesCommand = vendorIncrUpdates;
Dim vendorIncrUpdates As New SqlCommand()
With vendorIncrUpdates
    .CommandText = _
        "SELECT VendorId, VendorName, CreditRating, PreferredVendor " _
      & "FROM Sales.Vendor " _
      & "WHERE (UpdateTimestamp > @sync_last_received_anchor " _
      & "AND UpdateTimestamp <= @sync_new_received_anchor " _
      & "AND UpdateId <> @sync_originator_id " _
      & "AND NOT (InsertTimestamp > @sync_last_received_anchor " _
      & "AND InsertId <> @sync_originator_id))"
    .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
    .Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp)
    .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
    .Connection = serverConn
End With
vendorSyncAdapter.SelectIncrementalUpdatesCommand = vendorIncrUpdates

次のコード例では、クライアントからサーバーに更新を適用するコマンドを指定します。このコマンドには、アンカー変数と ID 変数に加えて、sync_force_write および sync_row_count variables が含まれています。

SqlCommand vendorUpdates = new SqlCommand();
vendorUpdates.CommandText =
    "UPDATE Sales.Vendor SET " + 
    "VendorName = @VendorName, CreditRating = @CreditRating, " + 
    "PreferredVendor = @PreferredVendor, " + 
    "UpdateId = @sync_originator_id " +           
    "WHERE (VendorId = @VendorId) " + 
    "AND (@sync_force_write = 1 " + 
    "OR (UpdateTimestamp <= @sync_last_received_anchor " +
    "OR UpdateId = @sync_originator_id)) " + 
    "SET @sync_row_count = @@rowcount";
vendorUpdates.Parameters.Add("@VendorName", SqlDbType.NVarChar);
vendorUpdates.Parameters.Add("@CreditRating", SqlDbType.NVarChar);
vendorUpdates.Parameters.Add("@PreferredVendor", SqlDbType.NVarChar);
vendorUpdates.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
vendorUpdates.Parameters.Add("@VendorId", SqlDbType.UniqueIdentifier);
vendorUpdates.Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit);
vendorUpdates.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
vendorUpdates.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);
vendorUpdates.Connection = serverConn;
vendorSyncAdapter.UpdateCommand = vendorUpdates;
Dim vendorUpdates As New SqlCommand()
With vendorUpdates
    .CommandText = _
        "UPDATE Sales.Vendor SET " _
      & "VendorName = @VendorName, CreditRating = @CreditRating, " _
      & "PreferredVendor = @PreferredVendor, " _
      & "UpdateId = @sync_originator_id " _
      & "WHERE (VendorId = @VendorId) " _
      & "AND (@sync_force_write = 1 " _
      & "OR (UpdateTimestamp <= @sync_last_received_anchor " _
      & "OR UpdateId = @sync_originator_id)) " _
      & "SET @sync_row_count = @@rowcount"
    .Parameters.Add("@VendorName", SqlDbType.NVarChar)
    .Parameters.Add("@CreditRating", SqlDbType.NVarChar)
    .Parameters.Add("@PreferredVendor", SqlDbType.NVarChar)
    .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
    .Parameters.Add("@VendorId", SqlDbType.UniqueIdentifier)
    .Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit)
    .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
    .Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int)
    .Connection = serverConn
End With
vendorSyncAdapter.UpdateCommand = vendorUpdates

次のコード例では、サーバーから増分削除を選択してクライアントに適用するコマンドを指定します。このコマンドには、アンカー パラメーターと ID パラメーターに加えて、sync_initialized 変数が含まれています。ここでは、その後の同期の場合のみ、廃棄テーブルから行が選択されます。最初の同期では、廃棄テーブル内の行は関係しません。

SqlCommand vendorIncrDeletes = new SqlCommand();
vendorIncrDeletes.CommandText =
    "SELECT VendorId, VendorName, CreditRating, PreferredVendor " +
    "FROM Sales.Vendor_Tombstone " +
    "WHERE (@sync_initialized = 1 " +
    "AND DeleteTimestamp > @sync_last_received_anchor " +
    "AND DeleteTimestamp <= @sync_new_received_anchor " +
    "AND DeleteId <> @sync_originator_id)";
vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncInitialized, SqlDbType.Bit);
vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp);
vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
vendorIncrDeletes.Connection = serverConn;
vendorSyncAdapter.SelectIncrementalDeletesCommand = vendorIncrDeletes;
Dim vendorIncrDeletes As New SqlCommand()
With vendorIncrDeletes
    .CommandText = _
        "SELECT VendorId, VendorName, CreditRating, PreferredVendor " _
      & "FROM Sales.Vendor_Tombstone " _
      & "WHERE (@sync_initialized = 1 " _
      & "AND DeleteTimestamp > @sync_last_received_anchor " _
      & "AND DeleteTimestamp <= @sync_new_received_anchor " _
      & "AND DeleteId <> @sync_originator_id)"
    .Parameters.Add("@" + SyncSession.SyncInitialized, SqlDbType.Bit)
    .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
    .Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp)
    .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
    .Connection = serverConn
End With
vendorSyncAdapter.SelectIncrementalDeletesCommand = vendorIncrDeletes

次のコード例では、クライアント ID を発信元 ID にマップするコマンドを指定します。これは必須ではありませんが、Sync Framework で使用されている GUID ではなく整数でクライアントを表すと便利な場合があります。ストアド プロシージャについては、次のコード例で説明します。

SqlCommand selectClientIdCommand = new SqlCommand();
selectClientIdCommand.CommandType = CommandType.StoredProcedure;
selectClientIdCommand.CommandText = "usp_GetOriginatorId";
selectClientIdCommand.Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier);
selectClientIdCommand.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int).Direction = ParameterDirection.Output;
selectClientIdCommand.Connection = serverConn;
this.SelectClientIdCommand = selectClientIdCommand;
Dim selectClientIdCommand As New SqlCommand()
With selectClientIdCommand
    .CommandType = CommandType.StoredProcedure
    .CommandText = "usp_GetOriginatorId"
    .Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier)
    .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int).Direction = ParameterDirection.Output
    .Connection = serverConn
End With
Me.SelectClientIdCommand = selectClientIdCommand

次のコード例では、マッピング テーブルと、そのテーブルのデータの読み取りおよび設定を実行するストアド プロシージャを作成します。このストアド プロシージャは、クライアント ID (GUID) を入力として受け取り、発信元 ID (整数) を返します。マッピング行がサーバーに挿入され、新しくクライアントが同期されるときに、行が追加されます。クライアントが一度同期されると、マッピング テーブルにはそのクライアントのエントリが含められます。SyncAdapter コマンドでは発信元 ID を使用するため、Vendor テーブルで追跡中の列は、uniqueidentifier 型ではなく int 型になります。

CREATE TABLE IdMapping(
    ClientId uniqueidentifier NOT NULL PRIMARY KEY, 
    OriginatorId int NOT NULL)
GO

--Insert a mapping for the server.
INSERT INTO IdMapping VALUES ('00000000-0000-0000-0000-000000000000', 0)
GO

CREATE PROCEDURE usp_GetOriginatorId
    @sync_client_id uniqueidentifier,
    @sync_originator_id int out

AS
     SELECT @sync_originator_id = OriginatorId FROM IdMapping WHERE ClientId = @sync_client_id 

     IF ( @sync_originator_id IS NULL )
     BEGIN
          SELECT @sync_originator_id = MAX(OriginatorId) + 1 FROM IdMapping
          INSERT INTO IdMapping VALUES (@sync_client_id, @sync_originator_id)
     END
GO

完全なコード例

次の完全なコード例には、既に説明したコード例に加え、同期を実行するためのコードが含まれています。この例では、「データベース プロバイダーの Utility クラスに関するトピック」で説明されている Utility クラスが必要です。

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 and client.
            Utility.MakeDataChangesOnServer("Vendor");
            Utility.MakeDataChangesOnClient("Vendor");

            //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();

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

    //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 command that enables you to pass in a 
            //client ID (a GUID) and get back the orginator ID (an integer) 
            //that is defined in a mapping table on the server.
            SqlCommand selectClientIdCommand = new SqlCommand();
            selectClientIdCommand.CommandType = CommandType.StoredProcedure;
            selectClientIdCommand.CommandText = "usp_GetOriginatorId";
            selectClientIdCommand.Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier);
            selectClientIdCommand.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int).Direction = ParameterDirection.Output;
            selectClientIdCommand.Connection = serverConn;
            this.SelectClientIdCommand = selectClientIdCommand;

            //Create a SyncAdapter for the Vendor table, and then define
            //the commands to synchronize changes:
            //* SelectIncrementalInsertsCommand, SelectIncrementalUpdatesCommand,
            //  and SelectIncrementalDeletesCommand are used to select changes
            //  from the server that the client provider then applies to the client.
            //* 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 vendorSyncAdapter = new SyncAdapter("Vendor");            
            
            //Select inserts from the server.
            //This command includes three session variables:
            //@sync_last_received_anchor, @sync_new_received_anchor,
            //and @sync_originator_id. The anchor variables are used with
            //SelectNewAnchorCommand to determine the set of changes to 
            //synchronize. In other example code, the commands use 
            //@sync_client_id instead of @sync_originator_id. In this case, 
            //@sync_originator_id is used because the SelectClientIdCommand 
            //is specified.
            SqlCommand vendorIncrInserts = new SqlCommand();
            vendorIncrInserts.CommandText =  
                "SELECT VendorId, VendorName, CreditRating, PreferredVendor " +
                "FROM Sales.Vendor " +
                "WHERE (InsertTimestamp > @sync_last_received_anchor " +
                "AND InsertTimestamp <= @sync_new_received_anchor " +
                "AND InsertId <> @sync_originator_id)";
            vendorIncrInserts.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
            vendorIncrInserts.Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp);
            vendorIncrInserts.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
            vendorIncrInserts.Connection = serverConn;
            vendorSyncAdapter.SelectIncrementalInsertsCommand = vendorIncrInserts;

            //Apply inserts to the server.
            //This command includes @sync_row_count, which returns
            //a count of how many rows were affected by the
            //last database operation. In SQL Server, the variable
            //is assigned the value of @@rowcount. The count is used
            //to determine whether an operation was successful or
            //was unsuccessful due to a conflict or an error.
            SqlCommand vendorInserts = new SqlCommand();
            vendorInserts.CommandText =
                "INSERT INTO Sales.Vendor (VendorId, VendorName, CreditRating, PreferredVendor, InsertId, UpdateId) " +
                "VALUES (@VendorId, @VendorName, @CreditRating, @PreferredVendor, @sync_originator_id, @sync_originator_id) " +
                "SET @sync_row_count = @@rowcount";
            vendorInserts.Parameters.Add("@VendorId", SqlDbType.UniqueIdentifier);
            vendorInserts.Parameters.Add("@VendorName", SqlDbType.NVarChar);
            vendorInserts.Parameters.Add("@CreditRating", SqlDbType.NVarChar);
            vendorInserts.Parameters.Add("@PreferredVendor", SqlDbType.NVarChar);
            vendorInserts.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
            vendorInserts.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);
            vendorInserts.Connection = serverConn;
            vendorSyncAdapter.InsertCommand = vendorInserts;
                                    
            
            //Select updates from the server
            SqlCommand vendorIncrUpdates = new SqlCommand();
            vendorIncrUpdates.CommandText =
                "SELECT VendorId, VendorName, CreditRating, PreferredVendor " +
                "FROM Sales.Vendor " +
                "WHERE (UpdateTimestamp > @sync_last_received_anchor " +
                "AND UpdateTimestamp <= @sync_new_received_anchor " +
                "AND UpdateId <> @sync_originator_id " +
                "AND NOT (InsertTimestamp > @sync_last_received_anchor " +
                "AND InsertId <> @sync_originator_id))";
            vendorIncrUpdates.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
            vendorIncrUpdates.Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp);
            vendorIncrUpdates.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
            vendorIncrUpdates.Connection = serverConn;
            vendorSyncAdapter.SelectIncrementalUpdatesCommand = vendorIncrUpdates;
            
            //Apply updates to the server.
            //This command includes @sync_force_write, which can
            //be used to apply changes in case of a conflict.
            SqlCommand vendorUpdates = new SqlCommand();
            vendorUpdates.CommandText =
                "UPDATE Sales.Vendor SET " + 
                "VendorName = @VendorName, CreditRating = @CreditRating, " + 
                "PreferredVendor = @PreferredVendor, " + 
                "UpdateId = @sync_originator_id " +           
                "WHERE (VendorId = @VendorId) " + 
                "AND (@sync_force_write = 1 " + 
                "OR (UpdateTimestamp <= @sync_last_received_anchor " +
                "OR UpdateId = @sync_originator_id)) " + 
                "SET @sync_row_count = @@rowcount";
            vendorUpdates.Parameters.Add("@VendorName", SqlDbType.NVarChar);
            vendorUpdates.Parameters.Add("@CreditRating", SqlDbType.NVarChar);
            vendorUpdates.Parameters.Add("@PreferredVendor", SqlDbType.NVarChar);
            vendorUpdates.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
            vendorUpdates.Parameters.Add("@VendorId", SqlDbType.UniqueIdentifier);
            vendorUpdates.Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit);
            vendorUpdates.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
            vendorUpdates.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);
            vendorUpdates.Connection = serverConn;
            vendorSyncAdapter.UpdateCommand = vendorUpdates;


            //Select deletes from the server.
            //This command includes @sync_initialized, which is
            //used to determine whether a client has been 
            //initialized already. If this variable returns 0,
            //this is the first synchronization for this client ID
            //or originator ID.
            SqlCommand vendorIncrDeletes = new SqlCommand();
            vendorIncrDeletes.CommandText =
                "SELECT VendorId, VendorName, CreditRating, PreferredVendor " +
                "FROM Sales.Vendor_Tombstone " +
                "WHERE (@sync_initialized = 1 " +
                "AND DeleteTimestamp > @sync_last_received_anchor " +
                "AND DeleteTimestamp <= @sync_new_received_anchor " +
                "AND DeleteId <> @sync_originator_id)";
            vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncInitialized, SqlDbType.Bit);
            vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
            vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp);
            vendorIncrDeletes.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
            vendorIncrDeletes.Connection = serverConn;
            vendorSyncAdapter.SelectIncrementalDeletesCommand = vendorIncrDeletes;

            //Apply deletes to the server.            
            SqlCommand vendorDeletes = new SqlCommand();
            vendorDeletes.CommandText =
                "DELETE FROM Sales.Vendor " +
                "WHERE (VendorId = @VendorId) " + 
                "AND (@sync_force_write = 1 " + 
                "OR (UpdateTimestamp <= @sync_last_received_anchor " + 
                "OR UpdateId = @sync_originator_id)) " + 
                "SET @sync_row_count = @@rowcount " + 
                "IF (@sync_row_count > 0)  BEGIN " + 
                "UPDATE Sales.Vendor_Tombstone " + 
                "SET DeleteId = @sync_originator_id " +
                "WHERE (VendorId = @VendorId) " + 
                "END";
            vendorDeletes.Parameters.Add("@VendorId", SqlDbType.UniqueIdentifier);       
            vendorDeletes.Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit);
            vendorDeletes.Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp);
            vendorDeletes.Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int);
            vendorDeletes.Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int);           
            vendorDeletes.Connection = serverConn;
            vendorSyncAdapter.DeleteCommand = vendorDeletes;     


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

        }
    }

    //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["Vendor"].Columns["VendorId"].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 server and client.
        Utility.MakeDataChangesOnServer("Vendor")
        Utility.MakeDataChangesOnClient("Vendor")

        '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()

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

    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 command that enables you to pass in a 
        'client ID (a GUID) and get back the orginator ID (an integer) 
        'that is defined in a mapping table on the server.
        Dim selectClientIdCommand As New SqlCommand()
        With selectClientIdCommand
            .CommandType = CommandType.StoredProcedure
            .CommandText = "usp_GetOriginatorId"
            .Parameters.Add("@" + SyncSession.SyncClientId, SqlDbType.UniqueIdentifier)
            .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int).Direction = ParameterDirection.Output
            .Connection = serverConn
        End With
        Me.SelectClientIdCommand = selectClientIdCommand

        'Create a SyncAdapter for the Vendor table, and then define
        'the commands to synchronize changes:
        '* SelectIncrementalInsertsCommand, SelectIncrementalUpdatesCommand,
        '  and SelectIncrementalDeletesCommand are used to select changes
        '  from the server that the client provider then applies to the client.
        '* 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 vendorSyncAdapter As New SyncAdapter("Vendor")

        'Select inserts from the server.
        'This command includes three session variables:
        '@sync_last_received_anchor, @sync_new_received_anchor,
        'and @sync_originator_id. The anchor variables are used with
        'SelectNewAnchorCommand to determine the set of changes to 
        'synchronize. In other example code, the commands use 
        '@sync_client_id instead of @sync_originator_id. In this case, 
        '@sync_originator_id is used because the SelectClientIdCommand 
        'is specified.
        Dim vendorIncrInserts As New SqlCommand()
        With vendorIncrInserts
            .CommandText = _
                "SELECT VendorId, VendorName, CreditRating, PreferredVendor " _
              & "FROM Sales.Vendor " _
              & "WHERE (InsertTimestamp > @sync_last_received_anchor " _
              & "AND InsertTimestamp <= @sync_new_received_anchor " _
              & "AND InsertId <> @sync_originator_id)"
            .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
            .Connection = serverConn
        End With
        vendorSyncAdapter.SelectIncrementalInsertsCommand = vendorIncrInserts

        'Apply inserts to the server.
        'This command includes @sync_row_count, which returns
        'a count of how many rows were affected by the
        'last database operation. In SQL Server, the variable
        'is assigned the value of @@rowcount. The count is used
        'to determine whether an operation was successful or
        'was unsuccessful due to a conflict or an error.
        Dim vendorInserts As New SqlCommand()
        With vendorInserts
            .CommandText = _
                "INSERT INTO Sales.Vendor (VendorId, VendorName, CreditRating, PreferredVendor, InsertId, UpdateId) " _
              & "VALUES (@VendorId, @VendorName, @CreditRating, @PreferredVendor, @sync_originator_id, @sync_originator_id) " _
              & "SET @sync_row_count = @@rowcount"
            .Parameters.Add("@VendorId", SqlDbType.UniqueIdentifier)
            .Parameters.Add("@VendorName", SqlDbType.NVarChar)
            .Parameters.Add("@CreditRating", SqlDbType.NVarChar)
            .Parameters.Add("@PreferredVendor", SqlDbType.NVarChar)
            .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
            .Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int)
            .Connection = serverConn
        End With
        vendorSyncAdapter.InsertCommand = vendorInserts

        'Select updates from the server
        Dim vendorIncrUpdates As New SqlCommand()
        With vendorIncrUpdates
            .CommandText = _
                "SELECT VendorId, VendorName, CreditRating, PreferredVendor " _
              & "FROM Sales.Vendor " _
              & "WHERE (UpdateTimestamp > @sync_last_received_anchor " _
              & "AND UpdateTimestamp <= @sync_new_received_anchor " _
              & "AND UpdateId <> @sync_originator_id " _
              & "AND NOT (InsertTimestamp > @sync_last_received_anchor " _
              & "AND InsertId <> @sync_originator_id))"
            .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
            .Connection = serverConn
        End With
        vendorSyncAdapter.SelectIncrementalUpdatesCommand = vendorIncrUpdates

        'Apply updates to the server.
        'This command includes @sync_force_write, which can
        'be used to apply changes in case of a conflict.
        Dim vendorUpdates As New SqlCommand()
        With vendorUpdates
            .CommandText = _
                "UPDATE Sales.Vendor SET " _
              & "VendorName = @VendorName, CreditRating = @CreditRating, " _
              & "PreferredVendor = @PreferredVendor, " _
              & "UpdateId = @sync_originator_id " _
              & "WHERE (VendorId = @VendorId) " _
              & "AND (@sync_force_write = 1 " _
              & "OR (UpdateTimestamp <= @sync_last_received_anchor " _
              & "OR UpdateId = @sync_originator_id)) " _
              & "SET @sync_row_count = @@rowcount"
            .Parameters.Add("@VendorName", SqlDbType.NVarChar)
            .Parameters.Add("@CreditRating", SqlDbType.NVarChar)
            .Parameters.Add("@PreferredVendor", SqlDbType.NVarChar)
            .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
            .Parameters.Add("@VendorId", SqlDbType.UniqueIdentifier)
            .Parameters.Add("@" + SyncSession.SyncForceWrite, SqlDbType.Bit)
            .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncRowCount, SqlDbType.Int)
            .Connection = serverConn
        End With
        vendorSyncAdapter.UpdateCommand = vendorUpdates

        'Select deletes from the server.
        'This command includes @sync_initialized, which is
        'used to determine whether a client has been 
        'initialized already. If this variable returns 0,
        'this is the first synchronization for this client ID
        'or originator ID.
        Dim vendorIncrDeletes As New SqlCommand()
        With vendorIncrDeletes
            .CommandText = _
                "SELECT VendorId, VendorName, CreditRating, PreferredVendor " _
              & "FROM Sales.Vendor_Tombstone " _
              & "WHERE (@sync_initialized = 1 " _
              & "AND DeleteTimestamp > @sync_last_received_anchor " _
              & "AND DeleteTimestamp <= @sync_new_received_anchor " _
              & "AND DeleteId <> @sync_originator_id)"
            .Parameters.Add("@" + SyncSession.SyncInitialized, SqlDbType.Bit)
            .Parameters.Add("@" + SyncSession.SyncLastReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncNewReceivedAnchor, SqlDbType.Timestamp)
            .Parameters.Add("@" + SyncSession.SyncOriginatorId, SqlDbType.Int)
            .Connection = serverConn
        End With
        vendorSyncAdapter.SelectIncrementalDeletesCommand = vendorIncrDeletes

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


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

    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("Vendor").Columns("VendorId").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

参照

概念

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