How to: Configure and Execute 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 the key parts of an application that uses Sync Framework to synchronize several databases. The code in this application focuses on 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.
As described in Architecture and Classes for Collaborative Synchronization, synchronization can occur between two instances of DbSyncProvider, two instances of SqlCeSyncProvider, or one instance of each. The example code in this topic is from a two-tier application; therefore it does not demonstrate synchronizing two instances of SqlCeSyncProvider, which requires an n-tier configuration. For an example of an n-tier configuration, see the sample WebSharingAppDemo-CEProviderEndToEnd that is included with the Sync Framework SDK.
Configuring synchronization involves the following steps:
Creating tracking tables to store metadata, and stored procedures to update data and metadata in each server database. For more information, see How to: Provision a Server Database for Collaborative Synchronization (Non-SQL Server).
Initializing each server database with schema, data, and change tracking infrastructure.
Executing synchronization involves the following steps:
Creating server synchronization adapters and a synchronization provider, and client synchronization provider.
Initializing each client database.
Creating a synchronization orchestrator, and synchronizing the nodes.
Initializing a Server Database
Initializing a database involves copying to each database the table schema and change tracking infrastructure, and any initial data that is required. For databases that are synchronized by using DbSyncProvider, Sync Framework does not automatically create table schema or tracking infrastructure in each database. An application must ensure that these objects exist before it tries to synchronize nodes. You can use backup and restore or another technology to copy the objects to each node, but you should do so only if changes are not occurring in the database from which the backup is taken. If the first database is in use and being updated, we strongly recommend that you copy only schema and change tracking infrastructure to each node, and use Sync Framework to copy the data. If you copy the data by using another method, a node might miss changes that have been committed at the first node. Sync Framework can initialize the data at each node as long as at least one node has the data. The example code in this topic uses this approach: each database contains two tables, but only the tables in SyncSamplesDb_Peer1 contain data. The data is copied to the other nodes during the first synchronization session.
For information about the initialization options for SqlCeSyncProvider, see Initializing a Client Database later in this topic.
Executing Synchronization
The code examples in this section are divided into the following categories:
The DbSyncAdapter object and commands for each table that will be synchronized in the server database.
The DbSyncProvider object and commands for the server.
The SqlCeSyncProvider object for the client.
The SyncSchema object and GenerateSnapshot method, which are used to initialize the client database.
The SyncOrchestrator object, which is used to synchronize the server and client databases.
Synchronization Adapter
The following properties are set on the DbSyncAdapter object for each table.
| Synchronization adapter property | Usage |
|---|---|
Specifies the primary key columns for the table. For example, if a |
|
Select all changes since the previous synchronization session by joining the base table and its change-tracking table. This is the maximum set of changes that could be synchronized. This set of changes might be reduced when synchronization knowledge is accounted for. |
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Apply to a node the inserts, updates, and deletes that were selected from another node. These changes were selected by using the query or procedure that you specified for the SelectIncrementalChangesCommand property. |
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InsertMetadataCommand, UpdateMetadataCommand, and DeleteMetadataCommand |
Update the change-tracking tables at a node to reflect the changes that were selected from the node and applied to another node. These updates enable Sync Framework to track where and when changes occurred. |
Select metadata for a row that is in conflict during synchronization. |
|
Select metadata that can be cleaned up at a node. Cleanup is typically retention-based: metadata is kept for a specific time. However, an application can use other logic to determine when to clean up metadata. For more information, see How to: Clean Up Metadata for Collaborative Synchronization (Non-SQL Server). |
The code examples in this section create commands that the DbSyncAdapter object executes during synchronization. These commands call the stored procedures that are described in How to: Provision a Server Database for Collaborative Synchronization (Non-SQL Server). The full set of commands is included in the complete code example at the end of this topic. In the code, parameters in the form "@" + DbSyncSession are session variables. For example, "@" + DbSyncSession.SyncMinTimestamp is a variable that resolves to a value of @sync_min_timestamp. For more information, see How to: Use Session Variables for Collaborative Synchronization (Non-SQL Server).
Application Code for SelectIncrementalChangesCommand
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;
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
Application Code for UpdateCommand
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;
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
Application Code for UpdateMetadataCommand
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;
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
Application Code for SelectRowCommand
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;
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
After all the commands are defined, the adapter is added to the provider by using the following code.
sampleProvider.SyncAdapters.Add(adapterCustomer);
Server Synchronization Provider
The following properties are set on the DbSyncProvider object for the server.
| Synchronization provider property | Usage |
|---|---|
The name of the scopes to synchronize for a particular session. Each scope should already exist in the scope information table in the server database. |
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The connection over which Sync Framework selects and applies changes to the server database. |
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Returns a timestamp value that is used to select and apply sets of changes to each database. During the current synchronization session, the command provides a new timestamp value. Changes that are made after the timestamp value from the previous synchronization session and before the new timestamp value are synchronized. The new value is then stored and used as the starting point for the next session. |
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Selects 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 the destination already has the changes, Sync Framework can often avoid running enumeration queries, which can improve performance. This property is optional; if a command is not specified, enumeration queries are executed for all tables. |
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Returns information from the scope information table, such as the synchronization knowledge and cleanup knowledge that Sync Framework requires. |
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Updates information in the scope information table. |
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Returns the scope name and table name for all tables in the specified scope that are also included in other scopes. |
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Updates the |
The code examples in this section create commands that the DbSyncProvider object executes during synchronization. The commands for the SelectScopeInfoCommand and UpdateScopeInfoCommand properties are included in the complete code example at the end of this topic.
Application Code for ScopeName and Connection
The following code example sets the name of the scope to synchronize, and the connection over which to synchronize. In the complete code example, the DbSyncProvider object contains a DbSyncAdapter object for the table Customer. When this table is synchronized for the first time, the definition of the Sales scope is set. After a scope has been synchronized for the first time, the scope should not be changed. Changing tables in the scope or filtering clauses for those tables can lead to non-convergence of data.
SqlConnection peerConnection = new SqlConnection(peerConnString);
sampleDbProvider.Connection = peerConnection;
sampleDbProvider.ScopeName = "Sales";
Dim peerConnection As New SqlConnection(peerConnString)
sampleDbProvider.Connection = peerConnection
sampleDbProvider.ScopeName = "Sales"
For more information about scopes, see "Define Scopes to Synchronize" in How to: Provision a Server Database for Collaborative Synchronization (Non-SQL Server).
Application Code for SelectNewTimestampCommand
The following code example creates a command for the SelectNewTimestampCommand property.
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;
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
Application Code for SelectTableMaxTimestampsCommand
The following code example creates a command for the SelectTableMaxTimestampsCommand property. In the complete code example, there are synchronization sessions in which no new changes have been made at either node. In these sessions, the call to SelectTableMaxTimestampsCommand indicates that no data changes are available to synchronize, so SelectIncrementalChangesCommand is not called.
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;
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
Client Synchronization Provider
The following code example creates a SqlCeSyncProvider object, sets the scope and connection, and registers event handlers. For the SqlCeSyncProvider, adapters are private and their commands are created automatically based on the schema that is initialized in the client database.
public SqlCeSyncProvider ConfigureCeSyncProvider(string sqlCeConnString)
{
SqlCeSyncProvider sampleCeProvider = new SqlCeSyncProvider();
//Set the scope name
sampleCeProvider.ScopeName = "Sales";
//Set the connection
sampleCeProvider.Connection = new SqlCeConnection(sqlCeConnString);
//Register event handlers
//Register the BeginSnapshotInitialization event handler.
//It is called when snapshot initialization is about to begin
//for a particular scope in a Compact database.
sampleCeProvider.BeginSnapshotInitialization += new EventHandler<DbBeginSnapshotInitializationEventArgs>(sampleCeProvider_BeginSnapshotInitialization);
//Register the EndSnapshotInitialization event handler.
//It is called when snapshot initialization has completed
//for a particular scope in a Compact database.
sampleCeProvider.EndSnapshotInitialization += new EventHandler<DbEndSnapshotInitializationEventArgs>(sampleCeProvider_EndSnapshotInitialization);
return sampleCeProvider;
}
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)
'Register event handlers
'Register the BeginSnapshotInitialization event handler.
'It is called when snapshot initialization is about to begin
'for a particular scope in a Compact database.
AddHandler sampleCeProvider.BeginSnapshotInitialization, AddressOf sampleCeProvider_BeginSnapshotInitialization
'Register the EndSnapshotInitialization event handler.
'It is called when snapshot initialization has completed
'for a particular scope in a Compact database.
AddHandler sampleCeProvider.EndSnapshotInitialization, AddressOf sampleCeProvider_EndSnapshotInitialization
Return sampleCeProvider
End Function
Initializing a Client Database
Before a SQL Server Compact client database can begin to receive changes from another database, the client database must contain table schema and any initial data, as well as the change-tracking infrastructure that Sync Framework requires. Sync Framework provides two ways to initialize the database:
Full initialization of the client database by using the server database
This enables tables to be created in the client database by using the tables, columns, and type description tables exposed by a DbSyncProvider object that connects to a server database instance. The client database is then prepared for synchronization, and all rows from the server database are downloaded as incremental inserts. The inserts are selected from the server by using the query or procedure that you specify for the SelectIncrementalChangesCommand property.
Snapshot initialization of the client database by using a pre-existing client database
Snapshot initialization is designed to reduce the time required to initialize a client database. After one client database has been initialized by using full initialization, subsequent databases can be initialized by using a snapshot of this first client database. A snapshot is a specially-prepared SQL Server Compact database that contains table schema, data (optional), and change-tracking infrastructure. Copy this snapshot to each client that requires it. During the first synchronization session for a client, client-specific metadata is updated, and any changes that occurred since the snapshot was created are downloaded to the client database.
Important
Snapshots should be generated only when there is no activity in the SQL Server Compact database. Concurrent operations of any type are not supported during snapshot generation.
The following code example performs full initialization. The code checks if a client database requires a schema each time synchronization occurs. If the provider has a connection to a client database that has already been initialized or is a snapshot database, the ScopeExists method returns true. If the method returns false, a schema is retrieved and applied to the client database by using the GetScopeDescription method.
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);
}
}
}
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
The following code example generates a snapshot. The code connects to a SQL Server Compact database that was just synchronized by using the sample's ConfigureCESyncProvider method. After connecting, the GenerateSnapshot method is called, which creates a copy of the original database. When the client provider subsequently connects to this new copy and synchronization is executed, the database is initialized.
//Second session: Synchronize two databases by using one instance of
//DbSyncProvider and one instance of SqlCeSyncProvider. After the Compact
//database is initialized, it is copied by using GenerateSnapshot and then
//used for the third session.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
//Copy the Compact database and save it as SyncSampleClient2.sdf.
SqlCeSyncStoreSnapshotInitialization snapshotInit = new SqlCeSyncStoreSnapshotInitialization();
snapshotInit.GenerateSnapshot(new SqlCeConnection(Utility.ConnStr_SqlCeSync1), "SyncSampleClient2.sdf");
//Make a change that is synchronized during the third session.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer");
//Third session: Synchronize the new Compact database. The five rows
//from SyncSampleClient1.sdf are already in SyncSampleClient2.sdf. The new
//change is now downloaded to bring SyncSampleClient2.sdf up to date.
//SyncSampleClient2.sdf will get this row during the next round of
//synchronization sessions.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
'Second session: Synchronize two databases by using one instance of
'DbSyncProvider and one instance of SqlCeSyncProvider. After the Compact
'database is initialized, it is copied by using GenerateSnapshot and then
'used for the third session.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
'Copy the Compact database and save it as SyncSampleClient2.sdf.
Dim snapshotInit As New SqlCeSyncStoreSnapshotInitialization()
snapshotInit.GenerateSnapshot(New SqlCeConnection(Utility.ConnStr_SqlCeSync1), "SyncSampleClient2.sdf")
'Make a change that is synchronized during the third session.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer")
'Third session: Synchronize the new Compact database. The five rows
'from SyncSampleClient1.sdf are already in SyncSampleClient2.sdf. The new
'change is now downloaded to bring SyncSampleClient2.sdf up to date.
'SyncSampleClient2.sdf will get this row during the next round of
'synchronization sessions.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
Note
In this example, the snapshot database is generated while the main application is running. In many cases, snapshots are generated at off-peak hours separately from other synchronization activity.
Creating a Synchronization Orchestrator and Synchronizing Databases
The code described in the previous sections of this topic demonstrates how to set the properties necessary for synchronization. Now it is time to synchronize nodes. Nodes are always synchronized as pairs, such as SyncSamplesDb_Peer1 and SyncSampleCe2. For a production application, a copy of the application would typically be deployed to each node so that synchronization could be initiated from any of the nodes.
The following code example creates a SampleSyncAgent class that derives from SyncOrchestrator. The SampleSyncAgent constructor takes two RelationalSyncProvider objects. Because DbSyncProvider and SqlCeSyncProvider both derive from RelationalSyncProvider, a SampleSyncAgent object can synchronize any combination of the two provider types. The code specifies which provider is the local provider and which is the remote provider. It then specifies that changes are first uploaded from the remote database to the local database and then downloaded in the other direction. The code checks if either of the providers are SqlCeSyncProvider objects that require schema initialization for a client database.
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 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
The following code sets up synchronization sessions by calling either ConfigureDbSyncProvider or ConfigureCeSyncProvider, methods that the sample application uses to set the appropriate provider properties for each session. The code then calls the Synchronize method of SampleSyncAgent to synchronize each pair of databases.
//The SampleStats class handles information from the SyncStatistics
//object that the Synchronize method returns.
SampleStats sampleStats = new SampleStats();
try
{
//Initial synchronization. Instantiate the SyncOrchestrator
//and call Synchronize.
SampleSyncProvider sampleSyncProvider = new SampleSyncProvider();
SyncOrchestrator sampleSyncAgent;
SyncOperationStatistics syncStatistics;
//First session: Synchronize two databases by using two instances
//of DbSyncProvider.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync2));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
//Second session: Synchronize two databases by using one instance of
//DbSyncProvider and one instance of SqlCeSyncProvider. After the Compact
//database is initialized, it is copied by using GenerateSnapshot and then
//used for the third session.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
//Copy the Compact database and save it as SyncSampleClient2.sdf.
SqlCeSyncStoreSnapshotInitialization snapshotInit = new SqlCeSyncStoreSnapshotInitialization();
snapshotInit.GenerateSnapshot(new SqlCeConnection(Utility.ConnStr_SqlCeSync1), "SyncSampleClient2.sdf");
//Make a change that is synchronized during the third session.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer");
//Third session: Synchronize the new Compact database. The five rows
//from SyncSampleClient1.sdf are already in SyncSampleClient2.sdf. The new
//change is now downloaded to bring SyncSampleClient2.sdf up to date.
//SyncSampleClient2.sdf will get this row during the next round of
//synchronization sessions.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2));
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);
}
'The SampleStats class handles information from the SyncStatistics
'object that the Synchronize method returns.
Dim sampleStats As New SampleStats()
Try
'Initial synchronization. Instantiate the SyncOrchestrator
'and call Synchronize.
Dim sampleSyncProvider As New SampleSyncProvider()
Dim sampleSyncAgent As SyncOrchestrator
Dim syncStatistics As SyncOperationStatistics
'First session: Synchronize two databases by using two instances
'of DbSyncProvider.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync2))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
'Second session: Synchronize two databases by using one instance of
'DbSyncProvider and one instance of SqlCeSyncProvider. After the Compact
'database is initialized, it is copied by using GenerateSnapshot and then
'used for the third session.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
'Copy the Compact database and save it as SyncSampleClient2.sdf.
Dim snapshotInit As New SqlCeSyncStoreSnapshotInitialization()
snapshotInit.GenerateSnapshot(New SqlCeConnection(Utility.ConnStr_SqlCeSync1), "SyncSampleClient2.sdf")
'Make a change that is synchronized during the third session.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer")
'Third session: Synchronize the new Compact database. The five rows
'from SyncSampleClient1.sdf are already in SyncSampleClient2.sdf. The new
'change is now downloaded to bring SyncSampleClient2.sdf up to date.
'SyncSampleClient2.sdf will get this row during the next round of
'synchronization sessions.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2))
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
Complete Code Example
The following complete code example includes the code examples that are described earlier and additional code to display synchronization statistics and event information. The example requires the Utility class that is available in Utility Class for Database Provider How-to Topics.
using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Data.SqlServerCe;
using Microsoft.Synchronization;
using Microsoft.Synchronization.Data;
using Microsoft.Synchronization.Data.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);
Utility.DeleteAndRecreateCompactDatabase(Utility.ConnStr_SqlCeSync2, false);
//The SampleStats class handles information from the SyncStatistics
//object that the Synchronize method returns.
SampleStats sampleStats = new SampleStats();
try
{
//Initial synchronization. Instantiate the SyncOrchestrator
//and call Synchronize.
SampleSyncProvider sampleSyncProvider = new SampleSyncProvider();
SyncOrchestrator sampleSyncAgent;
SyncOperationStatistics syncStatistics;
//First session: Synchronize two databases by using two instances
//of DbSyncProvider.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync2));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
//Second session: Synchronize two databases by using one instance of
//DbSyncProvider and one instance of SqlCeSyncProvider. After the Compact
//database is initialized, it is copied by using GenerateSnapshot and then
//used for the third session.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "initial");
//Copy the Compact database and save it as SyncSampleClient2.sdf.
SqlCeSyncStoreSnapshotInitialization snapshotInit = new SqlCeSyncStoreSnapshotInitialization();
snapshotInit.GenerateSnapshot(new SqlCeConnection(Utility.ConnStr_SqlCeSync1), "SyncSampleClient2.sdf");
//Make a change that is synchronized during the third session.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer");
//Third session: Synchronize the new Compact database. The five rows
//from SyncSampleClient1.sdf are already in SyncSampleClient2.sdf. The new
//change is now downloaded to bring SyncSampleClient2.sdf up to date.
//SyncSampleClient2.sdf will get this row during the next round of
//synchronization sessions.
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2));
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);
}
//Make a change in one of the databases.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync2, "Customer");
try
{
//Subsequent synchronization. Changes are now synchronized between all
//nodes.
SampleSyncProvider sampleSyncProvider = new SampleSyncProvider();
SyncOrchestrator sampleSyncAgent;
SyncOperationStatistics syncStatistics;
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync2));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "subsequent");
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1));
syncStatistics = sampleSyncAgent.Synchronize();
sampleStats.DisplayStats(syncStatistics, "subsequent");
sampleSyncAgent = new SampleSyncAgent(
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1),
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2));
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);
}
//Return data back to its original state.
Utility.CleanUpNode(Utility.ConnStr_DbSync1);
Utility.CleanUpNode(Utility.ConnStr_DbSync2);
//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);
//Register event handlers
//Register the BeginSnapshotInitialization event handler.
//It is called when snapshot initialization is about to begin
//for a particular scope in a Compact database.
sampleCeProvider.BeginSnapshotInitialization += new EventHandler<DbBeginSnapshotInitializationEventArgs>(sampleCeProvider_BeginSnapshotInitialization);
//Register the EndSnapshotInitialization event handler.
//It is called when snapshot initialization has completed
//for a particular scope in a Compact database.
sampleCeProvider.EndSnapshotInitialization += new EventHandler<DbEndSnapshotInitializationEventArgs>(sampleCeProvider_EndSnapshotInitialization);
return sampleCeProvider;
}
public void sampleCeProvider_CreatingSchema(object sender, CreatingSchemaEventArgs e)
{
Console.WriteLine("Full Initialization Process Started.....");
Console.WriteLine(
string.Format("CreatingSchame Event fired for Database {0}", e.Connection.Database)
);
}
public void sampleCeProvider_BeginSnapshotInitialization(object sender, DbBeginSnapshotInitializationEventArgs e)
{
Console.WriteLine("");
Console.WriteLine("Snapshot initialization process started");
Console.WriteLine(
string.Format("BeginSnapshotInitialization event fired for scope {0}", e.ScopeName)
);
}
public void sampleCeProvider_EndSnapshotInitialization(object sender, DbEndSnapshotInitializationEventArgs e)
{
Console.WriteLine("EndSnapshotInitialization event fired");
Dictionary<string, DbSnapshotInitializationTableStatistics> tableStats =
e.TableInitializationStatistics;
foreach (string tableName in tableStats.Keys)
{
DbSnapshotInitializationTableStatistics ts = tableStats[tableName];
Console.WriteLine("\tTable Name: " + tableName);
Console.WriteLine("\tTotal Rows: " + ts.TotalRows);
Console.WriteLine("\tRows Intialized: " + ts.RowsInitialized);
Console.WriteLine("\tStart Time: " + ts.StartTime);
Console.WriteLine("\tEnd Time: " + ts.EndTime);
}
Console.WriteLine("Snapshot initialization process completed");
Console.WriteLine("");
}
public DbSyncProvider ConfigureDbSyncProvider(string peerConnString)
{
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;
//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.
// There are additional commands related to metadata cleanup that are not
// included in this application.
//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;
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.Collections.Generic
Imports System.IO
Imports System.Text
Imports System.Data
Imports System.Data.SqlClient
Imports System.Data.SqlServerCe
Imports Microsoft.Synchronization
Imports Microsoft.Synchronization.Data
Imports Microsoft.Synchronization.Data.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 connection
'string information and making changes to the server database.
Utility.DeleteAndRecreateCompactDatabase(Utility.ConnStr_SqlCeSync1, True)
Utility.DeleteAndRecreateCompactDatabase(Utility.ConnStr_SqlCeSync2, False)
'The SampleStats class handles information from the SyncStatistics
'object that the Synchronize method returns.
Dim sampleStats As New SampleStats()
Try
'Initial synchronization. Instantiate the SyncOrchestrator
'and call Synchronize.
Dim sampleSyncProvider As New SampleSyncProvider()
Dim sampleSyncAgent As SyncOrchestrator
Dim syncStatistics As SyncOperationStatistics
'First session: Synchronize two databases by using two instances
'of DbSyncProvider.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync2))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
'Second session: Synchronize two databases by using one instance of
'DbSyncProvider and one instance of SqlCeSyncProvider. After the Compact
'database is initialized, it is copied by using GenerateSnapshot and then
'used for the third session.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "initial")
'Copy the Compact database and save it as SyncSampleClient2.sdf.
Dim snapshotInit As New SqlCeSyncStoreSnapshotInitialization()
snapshotInit.GenerateSnapshot(New SqlCeConnection(Utility.ConnStr_SqlCeSync1), "SyncSampleClient2.sdf")
'Make a change that is synchronized during the third session.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync1, "Customer")
'Third session: Synchronize the new Compact database. The five rows
'from SyncSampleClient1.sdf are already in SyncSampleClient2.sdf. The new
'change is now downloaded to bring SyncSampleClient2.sdf up to date.
'SyncSampleClient2.sdf will get this row during the next round of
'synchronization sessions.
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2))
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
'Make a change in one of the databases.
Utility.MakeDataChangesOnNode(Utility.ConnStr_DbSync2, "Customer")
Try
'Subsequent synchronization. Changes are now synchronized between all
'nodes.
Dim sampleSyncProvider As New SampleSyncProvider()
Dim sampleSyncAgent As SyncOrchestrator
Dim syncStatistics As SyncOperationStatistics
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync2))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "subsequent")
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync1))
syncStatistics = sampleSyncAgent.Synchronize()
sampleStats.DisplayStats(syncStatistics, "subsequent")
sampleSyncAgent = New SampleSyncAgent(sampleSyncProvider.ConfigureDbSyncProvider(Utility.ConnStr_DbSync1), _
sampleSyncProvider.ConfigureCeSyncProvider(Utility.ConnStr_SqlCeSync2))
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
'Return data back to its original state.
Utility.CleanUpNode(Utility.ConnStr_DbSync1)
Utility.CleanUpNode(Utility.ConnStr_DbSync2)
'Exit.
Console.Write(vbLf & "Press Enter to close the window.")
Console.ReadLine()
End Sub
'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)
'Register event handlers
'Register the BeginSnapshotInitialization event handler.
'It is called when snapshot initialization is about to begin
'for a particular scope in a Compact database.
AddHandler sampleCeProvider.BeginSnapshotInitialization, AddressOf sampleCeProvider_BeginSnapshotInitialization
'Register the EndSnapshotInitialization event handler.
'It is called when snapshot initialization has completed
'for a particular scope in a Compact database.
AddHandler sampleCeProvider.EndSnapshotInitialization, AddressOf sampleCeProvider_EndSnapshotInitialization
Return sampleCeProvider
End Function
Public Sub sampleCeProvider_CreatingSchema(ByVal sender As Object, ByVal e As CreatingSchemaEventArgs)
Console.WriteLine("Full initialization process started...")
Console.WriteLine(String.Format("CreatingSchema event fired for database {0}", e.Connection.Database))
End Sub
Public Sub sampleCeProvider_BeginSnapshotInitialization(ByVal sender As Object, ByVal e As DbBeginSnapshotInitializationEventArgs)
Console.WriteLine("")
Console.WriteLine("Snapshot initialization process started...")
Console.WriteLine(String.Format("BeginSnapshotInitialization event fired for scope {0}", e.ScopeName))
End Sub
Public Sub sampleCeProvider_EndSnapshotInitialization(ByVal sender As Object, ByVal e As DbEndSnapshotInitializationEventArgs)
Console.WriteLine("EndSnapshotInitialization event fired")
Dim tableStats As Dictionary(Of String, DbSnapshotInitializationTableStatistics) = e.TableInitializationStatistics
For Each tableName As String In tableStats.Keys
Dim ts As DbSnapshotInitializationTableStatistics = tableStats(tableName)
Console.WriteLine(vbTab & "Table Name: " & tableName)
Console.WriteLine(vbTab & "Total Rows: " & ts.TotalRows)
Console.WriteLine(vbTab & "Rows Intialized: " & ts.RowsInitialized)
Console.WriteLine(vbTab & "Start Time: " & ts.StartTime)
Console.WriteLine(vbTab & "End Time: " & ts.EndTime)
Next
Console.WriteLine("Snapshot initialization process completed")
Console.WriteLine("")
End Sub
Public Function ConfigureDbSyncProvider(ByVal peerConnString As String) 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
'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.
' There are additional commands related to metadata cleanup that are not
' included in this application.
'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
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
End Class
See Also
Concepts
How to: Provision a Server Database for Collaborative Synchronization (Non-SQL Server)
Synchronizing Other ADO.NET Compatible Databases