How to: Clean Up Metadata for Collaborative Synchronization (Non-SQL Server)
Note
The topics in this section of the documentation, Synchronizing Other ADO.NET Compatible Databases, are designed to demonstrate how databases other than SQL Server can be synchronized by using Sync Framework. In this release, SQL Server is used in code examples, but the code can be used for other ADO.NET compatible databases, with some modifications to the SQL Server-specific objects (such as SqlConnection) and the SQL queries that are shown. For information about SQL Server synchronization, see How to: Configure and Execute Collaborative Synchronization (SQL Server).
This topic describes how to clean up server metadata for peer-to-peer database synchronization in Sync Framework. The code in this topic describes the following Sync Framework classes:
For information about how to run sample code, see "Example Applications in the How to Topics" in Synchronizing Other ADO.NET Compatible Databases.
Understanding Metadata Cleanup
Cleanup involves deleting metadata for rows that have been deleted from a base table. Peer-to-peer synchronization uses two kinds of metadata:
Table-level metadata that tracks inserts, updates, and deletes for each table that is synchronized.
There is one row of metadata for each row in the base table. If a row is deleted from the base table and all nodes in all scopes have received it, the metadata row can be safely deleted.
Database-level metadata that tracks which changes each node has received from other nodes.
This metadata is typically stored in one scope table for each node database. Rows in the scope table should never be deleted unless the scope is dropped.
For more information about metadata, see "Create Tracking Tables for Per-Table Metadata" in How to: Provision a Server Database for Collaborative Synchronization (Non-SQL Server).
Metadata cleanup is handled by the application. For SQL Server Compact databases, use the SqlCeSyncStoreMetadataCleanup object:
The PerformCleanup is the method that you call from your application.
The RetentionInDays is the property that specifies how old change-tracking metadata must be, in days, for that metadata to be deleted when PerformCleanup is called.
For other databases, there are three components to metadata cleanup:
The CleanupMetadata method that you call from an application.
The command that you specify for the SelectMetadataForCleanupCommand property on the DbSyncAdapter object for each table. The CleanupMetadata method uses this command to select the rows that can be deleted.
The commands that you specify for the SelectOverlappingScopesCommand and UpdateScopeCleanupTimestampCommand properties:
The CleanupMetadata method uses SelectOverlappingScopesCommand before cleanup, to return the scope name and table name for all tables in the specified scope that are also included in other scopes.
The CleanupMetadata method uses UpdateScopeCleanupTimestampCommand after cleanup, to update the scope_cleanup_timestamp column for a particular scope in the scope_info table. This marks the point up to which cleanup has been performed for the scope.
Unlike other commands on the DbSyncAdapter object, the cleanup commands are not called automatically as part of each synchronization session. They are called only when an application calls the CleanupMetadata method. The command that you specify for the SelectMetadataForCleanupCommand property can use any logic that is appropriate to your application, but it is typically retention-based: metadata that is older than a particular length of time is deleted. If a node tries to synchronize changes whose metadata has already been cleaned up, an exception of type DbOutdatedSyncException is thrown. The SyncPeerOutdated event is raised, which provides access to a DbOutdatedEventArgs object. There are two options for handling this event:
Set the Action property to PartialSync. This synchronizes the data for which metadata is present, but some deletes are missed.
Set the Action property to AbortSync (the default). This ends the synchronization session. The client should be re-initialized in the next synchronization session so that it will have the correct data.
Key Parts of the API
The following code example specifies a command for the SelectMetadataForCleanupCommand property. The stored procedure that is called, sp_Customer_SelectMetadata, takes as a parameter a length of time in hours. This is the metadata retention period. Metadata that is older than this time period is cleaned up. If you pass a value of -1 to the procedure, all metadata is cleaned up, regardless of age.
Note
This example shows one approach to metadata cleanup. There is no requirement for the query or procedure to use a retention value as a parameter or to use -1 to indicate that all metadata should be cleaned up.
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
The following code example creates the stored procedure that is called by the cleanup command.
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
The following code example specifies a command for the SelectOverlappingScopesCommand property. This command and the next command (UpdateScopeCleanupTimestampCommand) enable Sync Framework to handle cleanup appropriately in cases where a table is included 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;
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
The following code example creates the stored procedure that is called by the overlapping scopes command.
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
The following code example specifies a command for the UpdateScopeCleanupTimestampCommand property.
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
The following code example calls the CleanupMetadata method. The code instantiates a provider and calls the ConfigureDbSyncProvider method in the SampleSyncProvider class. All the required DbSyncAdapter and DbSyncProvider properties are defined in this class. This includes the SelectMetadataForCleanupCommand property. The value of 7 that is passed to the ConfigureDbSyncProvider method is the metadata retention period in 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.");
}
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
Complete Code Example
The following complete code example includes the code examples that are described earlier and additional code to make changes and synchronize those changes. The code performs the following steps:
Synchronizes SyncSamplesDb_Peer1 (Node1) and SyncSamplesDb_Peer3 (Node3). Five rows are uploaded to Node3.
Synchronizes Node3 and SyncSampleCe1 (CeNode1).
Updates a row at Node1.
Calls CleanupMetadata for metadata that is more than 7 days old at Node1. The CleanupMetadata method returns successfully, but no metadata is cleaned up because no deletes have been made at Node1 that are older than 7 days.
Synchronizes Node1 and Node3. Synchronization is successful because all relevant metadata is still available at both nodes.
Deletes a row from Node3.
Calls CleanupMetadata for all metadata at Node3. The metadata for the delete in the previous step is cleaned up.
Synchronizes Node1 and Node3. Synchronization fails because the synchronization knowledge no longer matches the state of the node. An exception of type DbOutdatedSyncException is thrown.
It is important to clean up only the metadata that is no longer required by other nodes. If the second cleanup had occurred after Node1 had received the delete from Node3, synchronization would have succeeded.
Important
Running the following example code intentionally leaves the sample databases in an inconsistent state. After you run this code, drop the databases and re-create them by executing the script "Custom Change Tracking for Collaborative Scenarios" in Setup Scripts for Database Provider How-to Topics.
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