Как очищать метаданные для синхронизации совместной работы (Non-SQL Server)
.gif "Note") Примечание. |
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В разделе Синхронизация других баз данных, совместимых с ADO.NET демонстрируется, как можно выполнить синхронизацию баз данных, отличных от SQL Server, посредством Sync Framework. В этой версии в примерах кода используется SQL Server, но сам код можно использовать для других, совместимых с ADO.NET, баз данных с некоторыми изменениями специфических объектов SQL Server (например, SqlConnection) и отображаемых SQL-запросов. Дополнительные сведения о синхронизации SQL Server см. в разделе Как настроить и выполнить синхронизацию совместной работы (SQL Server). |
В этом разделе описывается, как очищать серверные метаданные для одноранговой синхронизации базы данных в Sync Framework. В коде из этого раздела описаны следующие классы Sync Framework.
Сведения о запуске образца кода см. в подразделе «Образцы приложений в разделах инструкций» раздела Синхронизация других баз данных, совместимых с ADO.NET.
Основные сведения об очистке метаданных
Очистка подразумевает удаление метаданных строк, которые были удалены из базовой таблицы. В одноранговой синхронизации используется следующие два типа метаданных.
Метаданные уровня таблиц, отслеживающие операции вставки, обновления и удаления для каждой синхронизируемой таблицы.
Для каждой строки базовой таблицы имеется одна строка метаданных. Если строка удаляется из базовой таблицы и ее получили все узлы во всех областях, то строку метаданных можно удалить.
Метаданные на уровне базы данных, которые отслеживают изменения, полученные каждым узлом с других узлов.
Эти метаданные обычно хранятся в одной таблице областей для каждой базы данных узла. Строки в таблице областей нельзя удалять, если не удаляется область.
Дополнительные сведения о метаданных см. в подразделе «Создание таблиц отслеживания для хранения метаданных на уровне таблиц» раздела Как подготовить серверную базу данных для синхронизации совместной работы (не SQL Server).
Очистка метаданных выполняется приложением. При работе с базами данных SQL Server Compact используйте объект SqlCeSyncStoreMetadataCleanup:
Метод PerformCleanup вызывается из приложения.
Свойство RetentionInDays указывает возраст метаданных отслеживания изменений (в днях), по достижении которого они удаляются при вызове метода PerformCleanup.
Для других баз данных очистка метаданных выполняется тремя компонентами.
Метод CleanupMetadata, который вызывается из приложения.
Команда, указываемая для свойства SelectMetadataForCleanupCommand в объекте DbSyncAdapter для каждой таблицы. С помощью этой команды метод CleanupMetadata выбирает строки, которые можно удалять.
Команды, указываемые для свойств SelectOverlappingScopesCommand и UpdateScopeCleanupTimestampCommand.
Метод CleanupMetadata использует SelectOverlappingScopesCommand перед очисткой, чтобы вернуть имя области и имя таблицы для всех таблиц в указанной области, которые также входят в другие области.
Метод CleanupMetadata использует UpdateScopeCleanupTimestampCommand после очистки, чтобы обновить столбец scope_cleanup_timestamp для определенной области в таблице scope_info. Таким образом отмечается момент, до которого выполнена очистка для области.
В отличие от других команд в объекте DbSyncAdapter, команды очистки не вызываются автоматически в ходе каждого сеанса синхронизации. Они вызываются только в случае, когда приложение вызывает метод CleanupMetadata. Команда, указанная для свойства SelectMetadataForCleanupCommand, может использовать любую логику, подходящую для приложения, но обычно основана на сроке хранения — удаляются метаданные, которые хранятся дольше определенного периода времени. Если узел пытается синхронизировать изменения, метаданные которых уже очищены, вызывается исключение типа DbOutdatedSyncException. Вызывается событие SyncPeerOutdated, которое предоставляет доступ к объекту DbOutdatedEventArgs. Это событие можно обрабатывать двумя способами.
Установите свойство Action в значение PartialSync. В этом случае будут синхронизированы данные, для которых имеются метаданные, однако некоторые операции удаления пропущены.
Установите свойство Action в значение AbortSync (по умолчанию). На этом сеанс синхронизации завершается. Клиент должен быть повторно инициализирован в следующем сеансе синхронизации, чтобы обеспечить правильность данных.
Ключевые компоненты API-интерфейса
В следующем примере кода указывается команда для свойства SelectMetadataForCleanupCommand. Вызываемая хранимая процедура, sp_Customer_SelectMetadata, принимает в качестве параметра протяженность времени в часах. Это срок хранения метаданных. Метаданные, старше этого периода, очищаются. Если передать процедуре значение -1, удаляются все метаданные, независимо от периода хранения.
| Примечание. |
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В этом примере показан один из методов очистки метаданных. Запрос или процедура не обязательно должны использовать в качестве параметра срок хранения или число -1, указывающее на необходимость очистки всех метаданных. |
SqlCommand selMetadataCustomerCmd = new SqlCommand();
selMetadataCustomerCmd.CommandType = CommandType.StoredProcedure;
selMetadataCustomerCmd.CommandText = "Sync.sp_Customer_SelectMetadata";
selMetadataCustomerCmd.Parameters.Add("@metadata_aging_in_days", SqlDbType.Int).Value = metadataAgingInDays;
selMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncScopeLocalId, SqlDbType.Int);
adapterCustomer.SelectMetadataForCleanupCommand = selMetadataCustomerCmd;
Dim selMetadataCustomerCmd As New SqlCommand()
selMetadataCustomerCmd.CommandType = CommandType.StoredProcedure
selMetadataCustomerCmd.CommandText = "Sync.sp_Customer_SelectMetadata"
selMetadataCustomerCmd.Parameters.Add("@metadata_aging_in_days", SqlDbType.Int).Value = metadataAgingInDays
selMetadataCustomerCmd.Parameters.Add("@" & DbSyncSession.SyncScopeLocalId, SqlDbType.Int)
adapterCustomer.SelectMetadataForCleanupCommand = selMetadataCustomerCmd
В следующем примере кода создается хранимая процедура, которая вызывается командой очистки.
CREATE PROCEDURE Sync.sp_Customer_SelectMetadata
@metadata_aging_in_days int,
@sync_scope_local_id int
AS
IF @metadata_aging_in_days = -1
BEGIN
SELECT CustomerId,
local_update_peer_timestamp as sync_row_timestamp,
case when (update_scope_local_id is null or update_scope_local_id <> @sync_scope_local_id)
then case when (restore_timestamp is null) then local_update_peer_timestamp else restore_timestamp end else scope_update_peer_timestamp end as sync_update_peer_timestamp,
case when (update_scope_local_id is null or update_scope_local_id <> @sync_scope_local_id)
then local_update_peer_key else scope_update_peer_key end as sync_update_peer_key,
case when (create_scope_local_id is null or create_scope_local_id <> @sync_scope_local_id)
then local_create_peer_timestamp else scope_create_peer_timestamp end as sync_create_peer_timestamp,
case when (create_scope_local_id is null or create_scope_local_id <> @sync_scope_local_id)
then local_create_peer_key else scope_create_peer_key end as sync_create_peer_key
FROM Sync.Customer_Tracking
WHERE sync_row_is_tombstone = 1
END
ELSE
BEGIN
SELECT CustomerId,
local_update_peer_timestamp as sync_row_timestamp,
case when (update_scope_local_id is null or update_scope_local_id <> @sync_scope_local_id)
then case when (restore_timestamp is null) then local_update_peer_timestamp else restore_timestamp end else scope_update_peer_timestamp end as sync_update_peer_timestamp,
case when (update_scope_local_id is null or update_scope_local_id <> @sync_scope_local_id)
then local_update_peer_key else scope_update_peer_key end as sync_update_peer_key,
case when (create_scope_local_id is null or create_scope_local_id <> @sync_scope_local_id)
then local_create_peer_timestamp else scope_create_peer_timestamp end as sync_create_peer_timestamp,
case when (create_scope_local_id is null or create_scope_local_id <> @sync_scope_local_id)
then local_create_peer_key else scope_create_peer_key end as sync_create_peer_key
FROM Sync.Customer_Tracking
WHERE sync_row_is_tombstone = 1 AND
DATEDIFF(day, last_change_datetime, GETDATE()) > @metadata_aging_in_days
END
В следующем примере кода указывается команда для свойства SelectOverlappingScopesCommand. Эта команда и следующая команда (UpdateScopeCleanupTimestampCommand) позволяют Sync Framework правильно выполнять очистку в случаях, когда таблица входит в несколько областей.
SqlCommand overlappingScopesCmd = new SqlCommand();
overlappingScopesCmd.CommandType = CommandType.StoredProcedure;
overlappingScopesCmd.CommandText = "Sync.sp_SelectSharedScopes";
overlappingScopesCmd.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100);
sampleDbProvider.SelectOverlappingScopesCommand = overlappingScopesCmd;
Dim overlappingScopesCmd As New SqlCommand()
With overlappingScopesCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_SelectSharedScopes"
.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100)
End With
sampleDbProvider.SelectOverlappingScopesCommand = overlappingScopesCmd
В следующем примере кода создается хранимая процедура, которая вызывается командой перекрывающихся областей.
CREATE PROCEDURE Sync.sp_SelectSharedScopes
@sync_scope_name nvarchar(100)
AS
SELECT ScopeTableMap2.table_name AS sync_table_name,
ScopeTableMap2.scope_name AS sync_shared_scope_name
FROM Sync.ScopeTableMap ScopeTableMap1 JOIN Sync.ScopeTableMap ScopeTableMap2
ON ScopeTableMap1.table_name = ScopeTableMap2.table_name
AND ScopeTableMap1.scope_name = @sync_scope_name
WHERE ScopeTableMap2.scope_name <> @sync_scope_name
В следующем примере кода указывается команда для свойства UpdateScopeCleanupTimestampCommand.
SqlCommand updScopeCleanupInfoCmd = new SqlCommand();
updScopeCleanupInfoCmd.CommandType = CommandType.Text;
updScopeCleanupInfoCmd.CommandText = "UPDATE scope_info set " +
" scope_cleanup_timestamp = @" + DbSyncSession.SyncScopeCleanupTimestamp +
" WHERE scope_name = @" + DbSyncSession.SyncScopeName +
" AND(scope_cleanup_timestamp is null or scope_cleanup_timestamp < @" + DbSyncSession.SyncScopeCleanupTimestamp + ");" +
" SET @" + DbSyncSession.SyncRowCount + " = @@rowcount";
updScopeCleanupInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeCleanupTimestamp, SqlDbType.BigInt);
updScopeCleanupInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100);
updScopeCleanupInfoCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
sampleDbProvider.UpdateScopeCleanupTimestampCommand = updScopeCleanupInfoCmd;
Dim updScopeCleanupInfoCmd As New SqlCommand()
With updScopeCleanupInfoCmd
.CommandType = CommandType.Text
.CommandText = "UPDATE scope_info set " _
& " scope_cleanup_timestamp = @" + DbSyncSession.SyncScopeCleanupTimestamp _
& " WHERE scope_name = @" + DbSyncSession.SyncScopeName _
& " AND(scope_cleanup_timestamp is null or scope_cleanup_timestamp < @" + DbSyncSession.SyncScopeCleanupTimestamp + ");" _
& " SET @" + DbSyncSession.SyncRowCount + " = @@rowcount"
.Parameters.Add("@" + DbSyncSession.SyncScopeCleanupTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100)
.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
End With
sampleDbProvider.UpdateScopeCleanupTimestampCommand = updScopeCleanupInfoCmd
В следующем примере кода вызывается метод CleanupMetadata. Код создает экземпляр поставщика и вызывает метод ConfigureDbSyncProvider в классе SampleSyncProvider. В этом классе определены все необходимые свойства DbSyncAdapter и DbSyncProvider. В том числе свойство SelectMetadataForCleanupCommand. Значение 7, которое передается методу ConfigureDbSyncProvider, является сроком хранения метаданных (в днях).
sampleSyncProvider = new SampleSyncProvider();
DbSyncProvider provider1 = sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1, 7);
if (provider1.CleanupMetadata() == true)
{
Console.WriteLine(String.Empty);
Console.WriteLine("Metadata cleanup ran in the SyncSamplesDb_Peer1 database.");
Console.WriteLine("Metadata more than 7 days old was deleted.");
}
else
{
Console.WriteLine("Metadata cleanup failed, most likely due to concurrency issues.");
}
sampleSyncProvider = New SampleSyncProvider()
Dim provider1 As DbSyncProvider = sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1, 7)
If provider1.CleanupMetadata() = True Then
Console.WriteLine([String].Empty)
Console.WriteLine("Metadata cleanup ran in the SyncSamplesDb_Peer1 database.")
Console.WriteLine("Metadata more than 7 days old was deleted.")
Else
Console.WriteLine("Metadata cleanup failed, most likely due to concurrency issues.")
End If
Полный пример кода
Приведенный ниже полный пример кода содержит все ранее описанные примеры и дополнительный код для выполнения изменений и их синхронизации. Код выполняет следующие действия.
Синхронизирует узлы SyncSamplesDb_Peer1 (Node1) и SyncSamplesDb_Peer3 (Node3). В узел Node3 передаются пять строк.
Синхронизирует узлы Node3 и SyncSampleCe1 (CeNode1).
Обновляет строку на узле Node1.
Вызывает метод CleanupMetadata для метаданных, срок хранения которых на узле Node1 превышает 7 дней. Метод CleanupMetadata успешно завершает работу, однако метаданные не очищаются, поскольку на узле Node1 не выполнялись операции удаления данных, созданных более 7 дней назад.
Синхронизирует узлы Node1 и Node3. Синхронизация выполняется успешно, поскольку все нужные метаданные все еще доступны на обоих узлах.
Удаляет строку с узла Node3.
Вызывает метод CleanupMetadata для всех метаданных на узле Node3. Очищаются метаданные удаления, выполненного в предыдущем шаге.
Синхронизирует узлы Node1 и Node3. Синхронизация завершается ошибкой, поскольку набор знаний синхронизации больше не соответствуют состоянию узла. Происходит исключение DbOutdatedSyncException.
Важно очищать только те метаданные, которые больше не требуются на других узлах. Если бы вторая очистка происходила после того, как узел Node1 получил удаление с узла Node3, синхронизация завершилась бы успешно.
| Внимание! |
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Код следующего примера намеренно оставляет образцы баз данных в несогласованном состоянии. После выполнения этого кода удалите базы данных и создайте их повторно, выполнив сценарий «Пользовательское отслеживание изменений для сценариев совместной работы» из раздела Инструкции по сценариям установки для поставщика базы данных. |
using System;
using System.IO;
using System.Collections.Generic;
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.SqlServerCe;
namespace Microsoft.Samples.Synchronization
{
class Program
{
static void Main(string[] args)
{
//The Utility class handles all functionality that is not
//directly related to synchronization, such as holding peerConnection
//string information and making changes to the server database.
Utility.DeleteAndRecreateCompactDatabase(Utility.ConnStr_SqlCeSync1, true);
//The SampleStats class handles information from the SyncStatistics
//object that the Synchronize method returns.
SampleStats sampleStats = new SampleStats();
SampleSyncProvider sampleSyncProvider = new SampleSyncProvider();
try
{
//Initial synchronization. Instantiate the SyncOrchestrator
//and call Synchronize.
sampleSyncProvider = new SampleSyncProvider();
SyncOrchestrator sampleSyncAgent;
SyncOperationStatistics syncStatistics;
//The integer passed to ConfigureDbSyncProvider is how old that metadata
//can be (in days) before it is deleted when CleanupMetadata() is called.
//The integer value is only relevant if CleanupMetadata() is called, as
//demonstrated later in this application.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1, 7),
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync3, 7));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync3, 7),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
}
catch (DbOutdatedSyncException ex)
{
Console.WriteLine("Outdated Knowledge: " + ex.OutdatedPeerSyncKnowledge.ToString() +
" Clean up knowledge: " + ex.MissingCleanupKnowledge.ToString());
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
//Update a row on peer 1.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer");
//Instantiate a provider, connect to peer 1, and delete tombstone metadata that
//is older than 7 days.
sampleSyncProvider = new SampleSyncProvider();
DbSyncProvider provider1 = sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1, 7);
if (provider1.CleanupMetadata() == true)
{
Console.WriteLine(String.Empty);
Console.WriteLine("Metadata cleanup ran in the SyncSamplesDb_Peer1 database.");
Console.WriteLine("Metadata more than 7 days old was deleted.");
}
else
{
Console.WriteLine("Metadata cleanup failed, most likely due to concurrency issues.");
}
//Synchronize.
try
{
SyncOrchestrator sampleSyncAgent;
SyncOperationStatistics syncStatistics;
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1, 7),
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync3, 7));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "subsequent");
}
catch (DbOutdatedSyncException ex)
{
Console.WriteLine("Outdated Knowledge: " + ex.OutdatedPeerSyncKnowledge.ToString() +
" Clean up knowledge: " + ex.MissingCleanupKnowledge.ToString());
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
//Delete a row on peer 3.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync3, "Customer");
//Instantiate a provider, connect to peer 3, and delete all tombstone metadata.
sampleSyncProvider = new SampleSyncProvider();
DbSyncProvider provider3 = sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync3, -1);
if (provider3.CleanupMetadata() == true)
{
Console.WriteLine(String.Empty);
Console.WriteLine("Metadata cleanup ran in the SyncSamplesDb_Peer3 database.");
Console.WriteLine("All metadata was deleted.");
}
else
{
Console.WriteLine("Metadata cleanup failed, most likely due to concurrency issues.");
}
//Synchronize.
try
{
SyncOrchestrator sampleSyncAgent;
SyncOperationStatistics syncStatistics;
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1, 7),
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync3, 7));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "subsequent");
}
catch (DbOutdatedSyncException ex)
{
Console.WriteLine(String.Empty);
Console.WriteLine("Synchronization failed due to outdated synchronization knowledge,");
Console.WriteLine("which is expected in this sample application.");
Console.WriteLine("Drop and recreate the sample databases.");
Console.WriteLine(String.Empty);
Console.WriteLine("Outdated Knowledge: " + ex.OutdatedPeerSyncKnowledge.ToString() +
" Clean up knowledge: " + ex.MissingCleanupKnowledge.ToString());
Console.WriteLine(String.Empty);
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
//Return peer data back to its original state.
Utility.CleanUpNode(Utility.ConnStr_DbSync1);
Utility.CleanUpNode(Utility.ConnStr_DbSync3);
//Exit.
Console.Write("\nPress Enter to close the window.");
Console.ReadLine();
}
}
//Create a class that is derived from
//Microsoft.Synchronization.SyncOrchestrator.
public class SampleSyncAgent : SyncOrchestrator
{
public SampleSyncAgent(RelationalSyncProvider localProvider, RelationalSyncProvider remoteProvider)
{
this.LocalProvider = localProvider;
this.RemoteProvider = remoteProvider;
this.Direction = SyncDirectionOrder.UploadAndDownload;
//Check to see if any provider is a SqlCe provider and if it needs to
//be initialized.
CheckIfProviderNeedsSchema(localProvider as SqlCeSyncProvider, remoteProvider as DbSyncProvider);
CheckIfProviderNeedsSchema(remoteProvider as SqlCeSyncProvider, localProvider as DbSyncProvider);
}
//For Compact databases that are not initialized with a snapshot,
//get the schema and initial data from a server database.
private void CheckIfProviderNeedsSchema(SqlCeSyncProvider providerToCheck, DbSyncProvider providerWithSchema)
{
//If one of the providers is a SqlCeSyncProvider and it needs
//to be initialized, retrieve the schema from the other provider
//if that provider is a DbSyncProvider; otherwise configure a
//DbSyncProvider, connect to the server, and retrieve the schema.
if (providerToCheck != null)
{
SqlCeSyncScopeProvisioning ceConfig = new SqlCeSyncScopeProvisioning();
SqlCeConnection ceConn = (SqlCeConnection)providerToCheck.Connection;
string scopeName = providerToCheck.ScopeName;
if (!ceConfig.ScopeExists(scopeName, ceConn))
{
DbSyncScopeDescription scopeDesc = providerWithSchema.GetScopeDescription();
ceConfig.PopulateFromScopeDescription(scopeDesc);
ceConfig.Apply(ceConn);
}
}
}
}
public class SampleSyncProvider
{
public SqlCeSyncProvider ConfigureCeSyncProvider(string sqlCeConnString)
{
SqlCeSyncProvider sampleCeProvider = new SqlCeSyncProvider();
//Set the scope name
sampleCeProvider.ScopeName = "Sales";
//Set the connection
sampleCeProvider.Connection = new SqlCeConnection(sqlCeConnString);
return sampleCeProvider;
}
public DbSyncProvider ConfigureDbSyncProvider(string peerConnString, int metadataAgingInDays)
{
DbSyncProvider sampleDbProvider = new DbSyncProvider();
SqlConnection peerConnection = new SqlConnection(peerConnString);
sampleDbProvider.Connection = peerConnection;
sampleDbProvider.ScopeName = "Sales";
//Create a DbSyncAdapter object for the Customer table and associate it
//with the DbSyncProvider. Following the DataAdapter style in ADO.NET,
//DbSyncAdapter is the equivalent for synchronization. The commands that
//are specified for the DbSyncAdapter object call stored procedures
//that are created in each peer database.
DbSyncAdapter adapterCustomer = new DbSyncAdapter("Customer");
//Specify the primary key, which Sync Framework uses
//to identify each row during synchronization.
adapterCustomer.RowIdColumns.Add("CustomerId");
//Specify the command to select incremental changes.
//In this command and other commands, session variables are
//used to pass information at runtime. DbSyncSession.SyncMetadataOnly
//and SyncMinTimestamp are two of the string constants that
//the DbSyncSession class exposes. You could also include
//@sync_metadata_only and @sync_min_timestamp directly in your
//queries:
//* sync_metadata_only is used by Sync Framework as an optimization
// in some queries.
//* The value of the sync_min_timestamp session variable is compared to
// values in the sync_row_timestamp column in the tracking table to
// determine which rows to select.
SqlCommand chgsCustomerCmd = new SqlCommand();
chgsCustomerCmd.CommandType = CommandType.StoredProcedure;
chgsCustomerCmd.CommandText = "Sync.sp_Customer_SelectChanges";
chgsCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncMetadataOnly, SqlDbType.Int);
chgsCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncMinTimestamp, SqlDbType.BigInt);
chgsCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncScopeLocalId, SqlDbType.Int);
chgsCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncInitialize, SqlDbType.Int);
adapterCustomer.SelectIncrementalChangesCommand = chgsCustomerCmd;
//Specify the command to insert rows.
//The sync_row_count session variable is used in this command
//and other commands to return a count of the rows affected by an operation.
//A count of 0 indicates that an operation failed.
SqlCommand insCustomerCmd = new SqlCommand();
insCustomerCmd.CommandType = CommandType.StoredProcedure;
insCustomerCmd.CommandText = "Sync.sp_Customer_ApplyInsert";
insCustomerCmd.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
insCustomerCmd.Parameters.Add("@CustomerName", SqlDbType.NVarChar);
insCustomerCmd.Parameters.Add("@SalesPerson", SqlDbType.NVarChar);
insCustomerCmd.Parameters.Add("@CustomerType", SqlDbType.NVarChar);
insCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
adapterCustomer.InsertCommand = insCustomerCmd;
//Specify the command to update rows.
//The value of the sync_min_timestamp session variable is compared to
//values in the sync_row_timestamp column in the tracking table to
//determine which rows to update.
SqlCommand updCustomerCmd = new SqlCommand();
updCustomerCmd.CommandType = CommandType.StoredProcedure;
updCustomerCmd.CommandText = "Sync.sp_Customer_ApplyUpdate";
updCustomerCmd.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
updCustomerCmd.Parameters.Add("@CustomerName", SqlDbType.NVarChar);
updCustomerCmd.Parameters.Add("@SalesPerson", SqlDbType.NVarChar);
updCustomerCmd.Parameters.Add("@CustomerType", SqlDbType.NVarChar);
updCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncMinTimestamp, SqlDbType.BigInt);
updCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
updCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncForceWrite, SqlDbType.Int);
adapterCustomer.UpdateCommand = updCustomerCmd;
//Specify the command to delete rows.
//The value of the sync_min_timestamp session variable is compared to
//values in the sync_row_timestamp column in the tracking table to
//determine which rows to delete.
SqlCommand delCustomerCmd = new SqlCommand();
delCustomerCmd.CommandType = CommandType.StoredProcedure;
delCustomerCmd.CommandText = "Sync.sp_Customer_ApplyDelete";
delCustomerCmd.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
delCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncMinTimestamp, SqlDbType.BigInt);
delCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
delCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncForceWrite, SqlDbType.Int);
adapterCustomer.DeleteCommand = delCustomerCmd;
//Specify the command to select any conflicting rows.
SqlCommand selRowCustomerCmd = new SqlCommand();
selRowCustomerCmd.CommandType = CommandType.StoredProcedure;
selRowCustomerCmd.CommandText = "Sync.sp_Customer_SelectRow";
selRowCustomerCmd.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
selRowCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncScopeLocalId, SqlDbType.Int);
adapterCustomer.SelectRowCommand = selRowCustomerCmd;
//Specify the command to insert metadata rows.
//The session variables in this command relate to columns in
//the tracking table.
SqlCommand insMetadataCustomerCmd = new SqlCommand();
insMetadataCustomerCmd.CommandType = CommandType.StoredProcedure;
insMetadataCustomerCmd.CommandText = "Sync.sp_Customer_InsertMetadata";
insMetadataCustomerCmd.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncScopeLocalId, SqlDbType.Int);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowTimestamp, SqlDbType.BigInt);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncCreatePeerKey, SqlDbType.Int);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncCreatePeerTimestamp, SqlDbType.BigInt);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncUpdatePeerKey, SqlDbType.Int);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncUpdatePeerTimestamp, SqlDbType.BigInt);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowIsTombstone, SqlDbType.Int);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncCheckConcurrency, SqlDbType.Int);
insMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
adapterCustomer.InsertMetadataCommand = insMetadataCustomerCmd;
//Specify the command to update metadata rows.
SqlCommand updMetadataCustomerCmd = new SqlCommand();
updMetadataCustomerCmd.CommandType = CommandType.StoredProcedure;
updMetadataCustomerCmd.CommandText = "Sync.sp_Customer_UpdateMetadata";
updMetadataCustomerCmd.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncScopeLocalId, SqlDbType.Int);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowTimestamp, SqlDbType.BigInt);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncCreatePeerKey, SqlDbType.Int);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncCreatePeerTimestamp, SqlDbType.BigInt);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncUpdatePeerKey, SqlDbType.Int);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncUpdatePeerTimestamp, SqlDbType.BigInt);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowIsTombstone, SqlDbType.Int);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncCheckConcurrency, SqlDbType.Int);
updMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
adapterCustomer.UpdateMetadataCommand = updMetadataCustomerCmd;
//Specify the command to delete metadata rows.
SqlCommand delMetadataCustomerCmd = new SqlCommand();
delMetadataCustomerCmd.CommandType = CommandType.StoredProcedure;
delMetadataCustomerCmd.CommandText = "Sync.sp_Customer_DeleteMetadata";
delMetadataCustomerCmd.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier);
delMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncCheckConcurrency, SqlDbType.Int);
delMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowTimestamp, SqlDbType.BigInt);
delMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
adapterCustomer.DeleteMetadataCommand = delMetadataCustomerCmd;
//Specify the command to select metadata rows for cleanup.
SqlCommand selMetadataCustomerCmd = new SqlCommand();
selMetadataCustomerCmd.CommandType = CommandType.StoredProcedure;
selMetadataCustomerCmd.CommandText = "Sync.sp_Customer_SelectMetadata";
selMetadataCustomerCmd.Parameters.Add("@metadata_aging_in_days", SqlDbType.Int).Value = metadataAgingInDays;
selMetadataCustomerCmd.Parameters.Add("@" + DbSyncSession.SyncScopeLocalId, SqlDbType.Int);
adapterCustomer.SelectMetadataForCleanupCommand = selMetadataCustomerCmd;
//Add the adapter to the provider.
sampleDbProvider.SyncAdapters.Add(adapterCustomer);
// Configure commands that relate to the provider itself rather
// than the DbSyncAdapter object for each table:
// * SelectNewTimestampCommand: Returns the new high watermark for
// the current synchronization session.
// * SelectScopeInfoCommand: Returns sync knowledge, cleanup knowledge,
// and a scope version (timestamp).
// * UpdateScopeInfoCommand: Sets new values for sync knowledge and cleanup knowledge.
// * SelectTableMaxTimestampsCommand (optional): Returns the maximum timestamp from each base table
// or tracking table, to determine whether for each table the destination already
// has all of the changes from the source. If a destination table has all the changes,
// SelectIncrementalChangesCommand is not called for that table.
// * SelectOverlappingScopesCommand: returns the scope name and table name for all tables
// in the specified scope that are also included in other scopes.
// * UpdateScopeCleanupTimestampCommand: updates the scope_cleanup_timestamp column for a
// particular scope in the scope_info table, to mark the point up to which cleanup
// has been performed for the scope.
//Select a new timestamp.
//During each synchronization, the new value and
//the last value from the previous synchronization
//are used: the set of changes between these upper and
//lower bounds is synchronized.
SqlCommand selectNewTimestampCommand = new SqlCommand();
string newTimestampVariable = "@" + DbSyncSession.SyncNewTimestamp;
selectNewTimestampCommand.CommandText = "SELECT " + newTimestampVariable + " = min_active_rowversion() - 1";
selectNewTimestampCommand.Parameters.Add(newTimestampVariable, SqlDbType.Timestamp);
selectNewTimestampCommand.Parameters[newTimestampVariable].Direction = ParameterDirection.Output;
sampleDbProvider.SelectNewTimestampCommand = selectNewTimestampCommand;
//Specify the command to select local replica metadata.
SqlCommand selReplicaInfoCmd = new SqlCommand();
selReplicaInfoCmd.CommandType = CommandType.Text;
selReplicaInfoCmd.CommandText = "SELECT " +
"scope_id, " +
"scope_local_id, " +
"scope_sync_knowledge, " +
"scope_tombstone_cleanup_knowledge, " +
"scope_timestamp " +
"FROM Sync.ScopeInfo " +
"WHERE scope_name = @" + DbSyncSession.SyncScopeName;
selReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100);
sampleDbProvider.SelectScopeInfoCommand = selReplicaInfoCmd;
//Specify the command to update local replica metadata.
SqlCommand updReplicaInfoCmd = new SqlCommand();
updReplicaInfoCmd.CommandType = CommandType.Text;
updReplicaInfoCmd.CommandText = "UPDATE Sync.ScopeInfo SET " +
"scope_sync_knowledge = @" + DbSyncSession.SyncScopeKnowledge + ", " +
"scope_id = @" + DbSyncSession.SyncScopeId + ", " +
"scope_tombstone_cleanup_knowledge = @" + DbSyncSession.SyncScopeCleanupKnowledge + " " +
"WHERE scope_name = @" + DbSyncSession.SyncScopeName + " AND " +
" ( @" + DbSyncSession.SyncCheckConcurrency + " = 0 OR scope_timestamp = @" + DbSyncSession.SyncScopeTimestamp + "); " +
"SET @" + DbSyncSession.SyncRowCount + " = @@rowcount";
updReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeKnowledge, SqlDbType.VarBinary, 10000);
updReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeCleanupKnowledge, SqlDbType.VarBinary, 10000);
updReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100);
updReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncCheckConcurrency, SqlDbType.Int);
updReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeId, SqlDbType.UniqueIdentifier);
updReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeTimestamp, SqlDbType.BigInt);
updReplicaInfoCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
sampleDbProvider.UpdateScopeInfoCommand = updReplicaInfoCmd;
//Return the maximum timestamp from the Customer_Tracking table.
//If more tables are synchronized, the query should UNION
//all of the results. The table name is not schema-qualified
//in this case because the name was not schema qualified in the
//DbSyncAdapter constructor.
SqlCommand selTableMaxTsCmd = new SqlCommand();
selTableMaxTsCmd.CommandType = CommandType.Text;
selTableMaxTsCmd.CommandText = "SELECT 'Customer' AS table_name, " +
"MAX(local_update_peer_timestamp) AS max_timestamp " +
"FROM Sync.Customer_Tracking";
sampleDbProvider.SelectTableMaxTimestampsCommand = selTableMaxTsCmd;
//Specify the command to select table and scope names for
//any tables that are in more than one scope.
SqlCommand overlappingScopesCmd = new SqlCommand();
overlappingScopesCmd.CommandType = CommandType.StoredProcedure;
overlappingScopesCmd.CommandText = "Sync.sp_SelectSharedScopes";
overlappingScopesCmd.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100);
sampleDbProvider.SelectOverlappingScopesCommand = overlappingScopesCmd;
//Specify the command that updates the scope information table
//to indicate to which point metadata has been cleaned up for a scope.
SqlCommand updScopeCleanupInfoCmd = new SqlCommand();
updScopeCleanupInfoCmd.CommandType = CommandType.Text;
updScopeCleanupInfoCmd.CommandText = "UPDATE scope_info set " +
" scope_cleanup_timestamp = @" + DbSyncSession.SyncScopeCleanupTimestamp +
" WHERE scope_name = @" + DbSyncSession.SyncScopeName +
" AND(scope_cleanup_timestamp is null or scope_cleanup_timestamp < @" + DbSyncSession.SyncScopeCleanupTimestamp + ");" +
" SET @" + DbSyncSession.SyncRowCount + " = @@rowcount";
updScopeCleanupInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeCleanupTimestamp, SqlDbType.BigInt);
updScopeCleanupInfoCmd.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100);
updScopeCleanupInfoCmd.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output;
sampleDbProvider.UpdateScopeCleanupTimestampCommand = updScopeCleanupInfoCmd;
return sampleDbProvider;
}
}
//Handle the statistics that are returned by the SyncAgent.
public class SampleStats
{
public void DisplayStats(SyncOperationStatistics 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.UploadChangesTotal);
Console.WriteLine("Total Changes Downloaded: " + syncStatistics.DownloadChangesTotal);
Console.WriteLine("Complete Time: " + syncStatistics.SyncEndTime);
Console.WriteLine(String.Empty);
}
}
}
Imports System
Imports System.IO
Imports System.Collections.Generic
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.SqlServerCe
Class Program
Shared Sub Main(ByVal args As String())
'The Utility class handles all functionality that is not
'directly related to synchronization, such as holding peerConnection
'string information and making changes to the server database.
Utility.DeleteAndRecreateCompactDatabase(Utility.ConnStr_SqlCeSync1, True)
'The SampleStats class handles information from the SyncStatistics
'object that the Synchronize method returns.
Dim sampleStats As New SampleStats()
Dim sampleSyncProvider As New SampleSyncProvider()
Try
'Initial synchronization. Instantiate the SyncOrchestrator
'and call Synchronize.
sampleSyncProvider = New SampleSyncProvider()
Dim sampleSyncAgent As SyncOrchestrator
Dim syncStatistics As SyncOperationStatistics
'The integer passed to ConfigureDbSyncProvider is how old that metadata
'can be (in days) before it is deleted when CleanupMetadata() is called.
'The integer value is only relevant if CleanupMetadata() is called, as
'demonstrated later in this application.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider( _
Utility.ConnStr_DbSync1, 7), _
sampleSyncProvider.ConfigureDbSyncProvider( _
Utility.ConnStr_DbSync3, 7))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider( _
Utility.ConnStr_DbSync3, 7), _
sampleSyncProvider.ConfigureCeSyncProvider( _
Utility.ConnStr_SqlCeSync1))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
Catch ex As DbOutdatedSyncException
Console.WriteLine(("Outdated Knowledge: " & ex.OutdatedPeerSyncKnowledge.ToString() _
& " Clean up knowledge: ") + ex.MissingCleanupKnowledge.ToString())
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
'Update a row on peer 1.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer")
'Instantiate a provider, connect to peer 1, and delete tombstone metadata that
'is older than 7 days.
sampleSyncProvider = New SampleSyncProvider()
Dim provider1 As DbSyncProvider = sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1, 7)
If provider1.CleanupMetadata() = True Then
Console.WriteLine([String].Empty)
Console.WriteLine("Metadata cleanup ran in the SyncSamplesDb_Peer1 database.")
Console.WriteLine("Metadata more than 7 days old was deleted.")
Else
Console.WriteLine("Metadata cleanup failed, most likely due to concurrency issues.")
End If
'Synchronize.
Try
Dim sampleSyncAgent As SyncOrchestrator
Dim syncStatistics As SyncOperationStatistics
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider( _
Utility.ConnStr_DbSync1, 7), _
sampleSyncProvider.ConfigureDbSyncProvider( _
Utility.ConnStr_DbSync3, 7))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "subsequent")
Catch ex As DbOutdatedSyncException
Console.WriteLine(("Outdated Knowledge: " & ex.OutdatedPeerSyncKnowledge.ToString() _
& " Clean up knowledge: ") + ex.MissingCleanupKnowledge.ToString())
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
'Delete a row on peer 3.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync3, "Customer")
'Instantiate a provider, connect to peer 3, and delete all tombstone metadata.
sampleSyncProvider = New SampleSyncProvider()
Dim provider3 As DbSyncProvider = sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync3, -1)
If provider3.CleanupMetadata() = True Then
Console.WriteLine([String].Empty)
Console.WriteLine("Metadata cleanup ran in the SyncSamplesDb_Peer3 database.")
Console.WriteLine("All metadata was deleted.")
Else
Console.WriteLine("Metadata cleanup failed, most likely due to concurrency issues.")
End If
'Synchronize.
Try
Dim sampleSyncAgent As SyncOrchestrator
Dim syncStatistics As SyncOperationStatistics
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider( _
Utility.ConnStr_DbSync1, 7), _
sampleSyncProvider.ConfigureDbSyncProvider( _
Utility.ConnStr_DbSync3, 7))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "subsequent")
Catch ex As DbOutdatedSyncException
Console.WriteLine([String].Empty)
Console.WriteLine("Synchronization failed due to outdated synchronization knowledge,")
Console.WriteLine("which is expected in this sample application.")
Console.WriteLine("Drop and recreate the sample databases.")
Console.WriteLine([String].Empty)
Console.WriteLine(("Outdated Knowledge: " & ex.OutdatedPeerSyncKnowledge.ToString() _
& " Clean up knowledge: ") + ex.MissingCleanupKnowledge.ToString())
Console.WriteLine([String].Empty)
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
'Return peer data back to its original state.
Utility.CleanUpNode(Utility.ConnStr_DbSync1)
Utility.CleanUpNode(Utility.ConnStr_DbSync3)
'Exit.
Console.Write(vbLf & "Press Enter to close the window.")
Console.ReadLine()
End Sub
End Class
'Create a class that is derived from
'Microsoft.Synchronization.SyncOrchestrator.
Public Class SampleSyncAgent
Inherits SyncOrchestrator
Public Sub New(ByVal localProvider As RelationalSyncProvider, ByVal _
remoteProvider As RelationalSyncProvider)
Me.LocalProvider = localProvider
Me.RemoteProvider = remoteProvider
Me.Direction = SyncDirectionOrder.UploadAndDownload
'Check to see if any provider is a SqlCe provider and if it needs to
'be initialized.
CheckIfProviderNeedsSchema(TryCast(localProvider, SqlCeSyncProvider), _
TryCast(remoteProvider, DbSyncProvider))
CheckIfProviderNeedsSchema(TryCast(remoteProvider, SqlCeSyncProvider), _
TryCast(localProvider, DbSyncProvider))
End Sub
'For Compact databases that are not initialized with a snapshot,
'get the schema and initial data from a server database.
Private Sub CheckIfProviderNeedsSchema(ByVal providerToCheck As SqlCeSyncProvider, _
ByVal providerWithSchema As DbSyncProvider)
'If one of the providers is a SqlCeSyncProvider and it needs
'to be initialized, retrieve the schema from the other provider
'if that provider is a DbSyncProvider; otherwise configure a
'DbSyncProvider, connect to the server, and retrieve the schema.
If providerToCheck IsNot Nothing Then
Dim ceConfig As New SqlCeSyncScopeProvisioning()
Dim ceConn As SqlCeConnection = DirectCast(providerToCheck.Connection, SqlCeConnection)
Dim scopeName As String = providerToCheck.ScopeName
If Not ceConfig.ScopeExists(scopeName, ceConn) Then
Dim scopeDesc As DbSyncScopeDescription = providerWithSchema.GetScopeDescription()
ceConfig.PopulateFromScopeDescription(scopeDesc)
ceConfig.Apply(ceConn)
End If
End If
End Sub
End Class
Public Class SampleSyncProvider
Public Function ConfigureCeSyncProvider(ByVal sqlCeConnString As String) As SqlCeSyncProvider
Dim sampleCeProvider As New SqlCeSyncProvider()
'Set the scope name
sampleCeProvider.ScopeName = "Sales"
'Set the connection
sampleCeProvider.Connection = New SqlCeConnection(sqlCeConnString)
Return sampleCeProvider
End Function
Public Function ConfigureDbSyncProvider(ByVal peerConnString As String, ByVal metadataAgingInDays As Integer) As DbSyncProvider
Dim sampleDbProvider As New DbSyncProvider()
Dim peerConnection As New SqlConnection(peerConnString)
sampleDbProvider.Connection = peerConnection
sampleDbProvider.ScopeName = "Sales"
'Create a DbSyncAdapter object for the Customer table and associate it
'with the DbSyncProvider. Following the DataAdapter style in ADO.NET,
'DbSyncAdapter is the equivalent for synchronization. The commands that
'are specified for the DbSyncAdapter object call stored procedures
'that are created in each peer database.
Dim adapterCustomer As New DbSyncAdapter("Customer")
'Specify the primary key, which Sync Framework uses
'to identify each row during synchronization.
adapterCustomer.RowIdColumns.Add("CustomerId")
'Specify the command to select incremental changes.
'In this command and other commands, session variables are
'used to pass information at runtime. DbSyncSession.SyncMetadataOnly
'and SyncMinTimestamp are two of the string constants that
'the DbSyncSession class exposes. You could also include
'@sync_metadata_only and @sync_min_timestamp directly in your
'queries:
'* sync_metadata_only is used by Sync Framework as an optimization
' in some queries.
'* The value of the sync_min_timestamp session variable is compared to
' values in the sync_row_timestamp column in the tracking table to
' determine which rows to select.
Dim chgsCustomerCmd As New SqlCommand()
With chgsCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_SelectChanges"
.Parameters.Add("@" & DbSyncSession.SyncMetadataOnly, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncMinTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncScopeLocalId, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncInitialize, SqlDbType.Int)
End With
adapterCustomer.SelectIncrementalChangesCommand = chgsCustomerCmd
'Specify the command to insert rows.
'The sync_row_count session variable is used in this command
'and other commands to return a count of the rows affected by an operation.
'A count of 0 indicates that an operation failed.
Dim insCustomerCmd As New SqlCommand()
With insCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_ApplyInsert"
.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
.Parameters.Add("@CustomerName", SqlDbType.NVarChar)
.Parameters.Add("@SalesPerson", SqlDbType.NVarChar)
.Parameters.Add("@CustomerType", SqlDbType.NVarChar)
.Parameters.Add("@" & DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
End With
adapterCustomer.InsertCommand = insCustomerCmd
'Specify the command to update rows.
'The value of the sync_min_timestamp session variable is compared to
'values in the sync_row_timestamp column in the tracking table to
'determine which rows to update.
Dim updCustomerCmd As New SqlCommand()
With updCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_ApplyUpdate"
.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
.Parameters.Add("@CustomerName", SqlDbType.NVarChar)
.Parameters.Add("@SalesPerson", SqlDbType.NVarChar)
.Parameters.Add("@CustomerType", SqlDbType.NVarChar)
.Parameters.Add("@" & DbSyncSession.SyncMinTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
.Parameters.Add("@" & DbSyncSession.SyncForceWrite, SqlDbType.Int)
End With
adapterCustomer.UpdateCommand = updCustomerCmd
'Specify the command to delete rows.
'The value of the sync_min_timestamp session variable is compared to
'values in the sync_row_timestamp column in the tracking table to
'determine which rows to delete.
Dim delCustomerCmd As New SqlCommand()
With delCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_ApplyDelete"
.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
.Parameters.Add("@" & DbSyncSession.SyncMinTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
.Parameters.Add("@" & DbSyncSession.SyncForceWrite, SqlDbType.Int)
End With
adapterCustomer.DeleteCommand = delCustomerCmd
'Specify the command to select any conflicting rows.
Dim selRowCustomerCmd As New SqlCommand()
With selRowCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_SelectRow"
.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
.Parameters.Add("@" & DbSyncSession.SyncScopeLocalId, SqlDbType.Int)
End With
adapterCustomer.SelectRowCommand = selRowCustomerCmd
'Specify the command to insert metadata rows.
'The session variables in this command relate to columns in
'the tracking table.
Dim insMetadataCustomerCmd As New SqlCommand()
With insMetadataCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_InsertMetadata"
.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
.Parameters.Add("@" & DbSyncSession.SyncScopeLocalId, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncRowTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncCreatePeerKey, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncCreatePeerTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncUpdatePeerKey, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncUpdatePeerTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncRowIsTombstone, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncCheckConcurrency, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
End With
adapterCustomer.InsertMetadataCommand = insMetadataCustomerCmd
'Specify the command to update metadata rows.
Dim updMetadataCustomerCmd As New SqlCommand()
With updMetadataCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_UpdateMetadata"
.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
.Parameters.Add("@" & DbSyncSession.SyncScopeLocalId, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncRowTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncCreatePeerKey, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncCreatePeerTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncUpdatePeerKey, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncUpdatePeerTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncRowIsTombstone, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncCheckConcurrency, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
End With
adapterCustomer.UpdateMetadataCommand = updMetadataCustomerCmd
'Specify the command to delete metadata rows.
Dim delMetadataCustomerCmd As New SqlCommand()
With delMetadataCustomerCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_Customer_DeleteMetadata"
.Parameters.Add("@CustomerId", SqlDbType.UniqueIdentifier)
.Parameters.Add("@" & DbSyncSession.SyncCheckConcurrency, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncRowTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
End With
adapterCustomer.DeleteMetadataCommand = delMetadataCustomerCmd
'Specify the command to select metadata rows for cleanup.
Dim selMetadataCustomerCmd As New SqlCommand()
selMetadataCustomerCmd.CommandType = CommandType.StoredProcedure
selMetadataCustomerCmd.CommandText = "Sync.sp_Customer_SelectMetadata"
selMetadataCustomerCmd.Parameters.Add("@metadata_aging_in_days", SqlDbType.Int).Value = metadataAgingInDays
selMetadataCustomerCmd.Parameters.Add("@" & DbSyncSession.SyncScopeLocalId, SqlDbType.Int)
adapterCustomer.SelectMetadataForCleanupCommand = selMetadataCustomerCmd
'Add the adapter to the provider.
sampleDbProvider.SyncAdapters.Add(adapterCustomer)
' Configure commands that relate to the provider itself rather
' than the DbSyncAdapter object for each table:
' * SelectNewTimestampCommand: Returns the new high watermark for
' the current synchronization session.
' * SelectScopeInfoCommand: Returns sync knowledge, cleanup knowledge,
' and a scope version (timestamp).
' * UpdateScopeInfoCommand: Sets new values for sync knowledge and cleanup knowledge.
' * SelectTableMaxTimestampsCommand (optional): Returns the maximum timestamp from each base table
' or tracking table, to determine whether for each table the destination already
' has all of the changes from the source. If a destination table has all the changes,
' SelectIncrementalChangesCommand is not called for that table.
' * SelectOverlappingScopesCommand: returns the scope name and table name for all tables
' in the specified scope that are also included in other scopes.
' * UpdateScopeCleanupTimestampCommand: updates the scope_cleanup_timestamp column for a
' particular scope in the scope_info table, to mark the point up to which cleanup
' has been performed for the scope.
'Select a new timestamp.
'During each synchronization, the new value and
'the last value from the previous synchronization
'are used: the set of changes between these upper and
'lower bounds is synchronized.
Dim selectNewTimestampCommand As New SqlCommand()
Dim newTimestampVariable As String = "@" & DbSyncSession.SyncNewTimestamp
With selectNewTimestampCommand
.CommandText = "SELECT " & newTimestampVariable & " = min_active_rowversion() - 1"
.Parameters.Add(newTimestampVariable, SqlDbType.Timestamp)
.Parameters(newTimestampVariable).Direction = ParameterDirection.Output
End With
sampleDbProvider.SelectNewTimestampCommand = selectNewTimestampCommand
'Specify the command to select local replica metadata.
Dim selReplicaInfoCmd As New SqlCommand()
With selReplicaInfoCmd
.CommandType = CommandType.Text
.CommandText = "SELECT " _
& "scope_id, " _
& "scope_local_id, " _
& "scope_sync_knowledge, " _
& "scope_tombstone_cleanup_knowledge, " _
& "scope_timestamp " _
& "FROM Sync.ScopeInfo " _
& "WHERE scope_name = @" + DbSyncSession.SyncScopeName
.Parameters.Add("@" & DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100)
End With
sampleDbProvider.SelectScopeInfoCommand = selReplicaInfoCmd
'Specify the command to update local replica metadata.
Dim updReplicaInfoCmd As New SqlCommand()
With updReplicaInfoCmd
.CommandType = CommandType.Text
.CommandText = "UPDATE Sync.ScopeInfo SET " _
& "scope_sync_knowledge = @" + DbSyncSession.SyncScopeKnowledge + ", " _
& "scope_id = @" + DbSyncSession.SyncScopeId + ", " _
& "scope_tombstone_cleanup_knowledge = @" + DbSyncSession.SyncScopeCleanupKnowledge + " " _
& "WHERE scope_name = @" + DbSyncSession.SyncScopeName + " AND " _
& " ( @" + DbSyncSession.SyncCheckConcurrency + " = 0 OR scope_timestamp = @" + DbSyncSession.SyncScopeTimestamp + "); " _
& "SET @" + DbSyncSession.SyncRowCount + " = @@rowcount"
.Parameters.Add("@" & DbSyncSession.SyncScopeKnowledge, SqlDbType.VarBinary, 10000)
.Parameters.Add("@" & DbSyncSession.SyncScopeCleanupKnowledge, SqlDbType.VarBinary, 10000)
.Parameters.Add("@" & DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100)
.Parameters.Add("@" & DbSyncSession.SyncCheckConcurrency, SqlDbType.Int)
.Parameters.Add("@" & DbSyncSession.SyncScopeId, SqlDbType.UniqueIdentifier)
.Parameters.Add("@" & DbSyncSession.SyncScopeTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" & DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
End With
sampleDbProvider.UpdateScopeInfoCommand = updReplicaInfoCmd
'Return the maximum timestamp from the Customer_Tracking table.
'If more tables are synchronized, the query should UNION
'all of the results. The table name is not schema-qualified
'in this case because the name was not schema qualified in the
'DbSyncAdapter constructor.
Dim selTableMaxTsCmd As New SqlCommand()
selTableMaxTsCmd.CommandType = CommandType.Text
selTableMaxTsCmd.CommandText = "SELECT 'Customer' AS table_name, " _
& "MAX(local_update_peer_timestamp) AS max_timestamp " _
& "FROM Sync.Customer_Tracking"
sampleDbProvider.SelectTableMaxTimestampsCommand = selTableMaxTsCmd
'Specify the command to select table and scope names for
'any tables that are in more than one scope.
Dim overlappingScopesCmd As New SqlCommand()
With overlappingScopesCmd
.CommandType = CommandType.StoredProcedure
.CommandText = "Sync.sp_SelectSharedScopes"
.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100)
End With
sampleDbProvider.SelectOverlappingScopesCommand = overlappingScopesCmd
'Specify the command that updates the scope information table
'to indicate to which point metadata has been cleaned up for a scope.
Dim updScopeCleanupInfoCmd As New SqlCommand()
With updScopeCleanupInfoCmd
.CommandType = CommandType.Text
.CommandText = "UPDATE scope_info set " _
& " scope_cleanup_timestamp = @" + DbSyncSession.SyncScopeCleanupTimestamp _
& " WHERE scope_name = @" + DbSyncSession.SyncScopeName _
& " AND(scope_cleanup_timestamp is null or scope_cleanup_timestamp < @" + DbSyncSession.SyncScopeCleanupTimestamp + ");" _
& " SET @" + DbSyncSession.SyncRowCount + " = @@rowcount"
.Parameters.Add("@" + DbSyncSession.SyncScopeCleanupTimestamp, SqlDbType.BigInt)
.Parameters.Add("@" + DbSyncSession.SyncScopeName, SqlDbType.NVarChar, 100)
.Parameters.Add("@" + DbSyncSession.SyncRowCount, SqlDbType.Int).Direction = ParameterDirection.Output
End With
sampleDbProvider.UpdateScopeCleanupTimestampCommand = updScopeCleanupInfoCmd
Return sampleDbProvider
End Function
End Class
'Handle the statistics that are returned by the SyncAgent.
Public Class SampleStats
Public Sub DisplayStats(ByVal syncStatistics As SyncOperationStatistics, 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.UploadChangesTotal)
Console.WriteLine("Total Changes Downloaded: " & syncStatistics.DownloadChangesTotal)
Console.WriteLine("Complete Time: " & syncStatistics.SyncEndTime)
Console.WriteLine([String].Empty)
End Sub
End Class