private void Run(string[] args)
{
string service = "8001";
bool ftEnable = false;
// Check the correct number of arguments have been supplied
if (args.Length > 2)
{
Console.WriteLine("usage: {0} [<data service> [FT]]", System.AppDomain.CurrentDomain.FriendlyName);
return;
}
// Check whether a service argument has been supplied
if (args.Length >= 1)
{
service = args[0];
}
// Check wether an FT argument has been supplied
if (args.Length >= 2)
{
ftEnable = args[1].Equals("FT");
}
// Build a connection string and connect to the database
PolyConnectionStringBuilder builder = new PolyConnectionStringBuilder();
builder.Service = service;
// Set FT connection settings
builder.FTEnable = ftEnable;
builder.FTHeartbeatInterval = 1000;
builder.FTHeartbeatTimeout = 1000;
builder.FTReconnectionCount = 1000;
builder.FTReconnectionInterval = 1000;
builder.FTReconnectionTimeout = 1000;
PolyConnection connection = new PolyConnection(builder.ConnectionString);
// Register for state change events on the connection
// This is used to detect loss of connection to the database
connection.StateChange += OnStateChange;
// Register for FT mode change events on the connection
connection.FTModeChange += OnFTModeChange;
Console.WriteLine("Connecting to {0}{1}...", service, ftEnable ? " Fault Tolerant" : "");
try
{
connection.Open();
}
catch (Exception)
{
Console.WriteLine("Failed to connect to database");
return;
}
// Create and command and an active adapter to perform the active query
Console.WriteLine("Connected, now launch active query...");
PolyCommand command = new PolyCommand("select code,usdollar from currency", connection);
PolyActiveDataAdapter adapter = new PolyActiveDataAdapter(command);
// Primary key information must be added to the data table
adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;
DataSet dataSet = new DataSet();
// Perform an initial fill of the data table
adapter.Fill(dataSet, "currency");
DataTable dataTable = dataSet.Tables["currency"];
// Display the results of the initial fill
WriteTable(dataTable);
// Register for data change events
// This indicates when a delta is available for the active query
adapter.DataChange += OnDataChange;
// Register for row changed and row deleted events on the data table
// This is used to determine the changes made when applying a delta
dataTable.RowChanged += OnRowChanged;
dataTable.RowDeleted += OnRowDeleted;
// Explicitly accept changes made to the data table by the delta
adapter.AcceptChangesDuringFill = false;
// Use the Upsert LoadOption to determine the changes made by the delta
adapter.FillLoadOption = LoadOption.Upsert;
while (WaitHandle.WaitOne())
{
// Stop when connection to the database is lost
if (connection.State == ConnectionState.Closed)
{
break;
}
// Apply the delta to the data table
adapter.FillDelta(dataTable);
Console.WriteLine("Delta complete - success.\n");
// Accept the changes made to the data table by the delta
dataTable.AcceptChanges();
}
connection.Close();
}
private void PolyForm_Load(object sender, EventArgs args)
{
// Build a connection string and connect to the database
PolyConnectionStringBuilder builder = new PolyConnectionStringBuilder();
builder.Service = service;
connection = new PolyConnection(builder.ConnectionString);
DialogResult result = DialogResult.Retry;
// Allow connection attempt to be retried if it fails
while (result == DialogResult.Retry)
{
try
{
connection.Open();
break;
}
catch (Exception exception)
{
result = MessageBox.Show(GetExceptionMessage(exception), Text, MessageBoxButtons.RetryCancel);
if (result != DialogResult.Retry)
{
Close();
return;
}
}
}
// Create an active data adapter to perform the active query (on the currency table)
dataAdapter = new PolyActiveDataAdapter("select * from currency", connection);
// Create a data table to hold the data
dataTable = new DataTable();
// Primary key information must be added to the data table
dataAdapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;
// Register for data change events
// This indicates when a delta is available for the active query
dataAdapter.DataChange += OnDataChange;
// Do not automatically accept changes made to the data table when updating
dataAdapter.AcceptChangesDuringUpdate = false;
// Start active query and obtain initial data
dataAdapter.Fill(dataTable);
// Provide the data table as the data source to the data grid
dataGridView.DataSource = dataTable;
// Sort data by currency code
dataGridView.Sort(dataGridView.Columns["code"], ListSortDirection.Ascending);
// Right-align column containing dollar value
dataGridView.Columns["usdollar"].DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleRight;
// Turn edit mode off
SetEditMode(false);
// Note that the connection must remain open for the active data adapter to function
}
private void Run(string[] args)
{
string service = "8001";
// Check the correct number of arguments have been supplied
if (args.Length > 2)
{
Console.WriteLine("usage: {0} <max size of load_file> [<data service>]", System.AppDomain.CurrentDomain.FriendlyName);
return;
}
// Maximum file size allowed
MaxFileSize = long.Parse(args[0]);
// Check whether a service argument has been supplied
if (args.Length >= 2)
{
service = args[1];
}
// Build a connection string and connect to the database
PolyConnectionStringBuilder builder = new PolyConnectionStringBuilder();
builder.Service = service;
Connection = new PolyConnection(builder.ConnectionString);
// Register for state change events on the connection
// This is used to detect loss of connection to the database
Connection.StateChange += OnStateChange;
Console.WriteLine("Connecting to database at {0}...", service);
try
{
Connection.Open();
}
catch (Exception)
{
Console.WriteLine("Failed to connect to database");
return;
}
// Create and command and an active adapter to perform the active query
Console.WriteLine("Connected, now launch active query on journal control");
Console.WriteLine("and monitor file_size for it reaching {0}", MaxFileSize);
PolyCommand command = new PolyCommand("select id,file_size from journalcontrol", Connection);
PolyActiveDataAdapter adapter = new PolyActiveDataAdapter(command);
// Primary key information must be added to the data table
adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;
DataSet dataSet = new DataSet();
// Perform an initial fill of the data table
adapter.Fill(dataSet, "journalcontrol");
DataTable dataTable = dataSet.Tables["journalcontrol"];
// Display the results of the initial fill
WriteTable(dataTable);
// Register for data change events
// This indicates when a delta is available for the active query
adapter.DataChange += OnDataChange;
while (WaitHandle.WaitOne())
{
// Stop when connection to the database is lost
if (Connection.State == ConnectionState.Closed)
{
break;
}
// Apply the delta to the data table
adapter.FillDelta(dataTable);
// Display the results of the delta
WriteTable(dataTable);
}
Connection.Close();
}
private void Run(string[] args)
{
string service = "8001";
// Check the correct number of arguments have been supplied
if (args.Length > 1)
{
Console.WriteLine("usage: {0} [<data service>]", System.AppDomain.CurrentDomain.FriendlyName);
return;
}
// Check whether a service argument has been supplied
if (args.Length >= 1)
{
service = args[0];
}
// Build a connection string and connect to the database
PolyConnectionStringBuilder builder = new PolyConnectionStringBuilder();
builder.Service = service;
PolyConnection connection = new PolyConnection(builder.ConnectionString);
// Register for state change events on the connection
// This is used to detect loss of connection to the database
connection.StateChange += OnStateChange;
Console.WriteLine("Connecting to {0}...", service);
try
{
connection.Open();
}
catch (Exception)
{
Console.WriteLine("Failed to connect to database");
return;
}
// Create and command and an active adapter to perform the active query
Console.WriteLine("Connected, now launch active query...");
PolyCommand command = new PolyCommand("select code,usdollar,low_limit,high_limit from currency_limits", connection);
PolyActiveDataAdapter adapter = new PolyActiveDataAdapter(command);
// Primary key information must be added to the data table
adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;
DataSet dataSet = new DataSet();
// Explicitly accept changes made to the data table by the delta
adapter.AcceptChangesDuringFill = false;
// Register for data change events
// This indicates when a delta is available for the active query
adapter.DataChange += OnDataChange;
// Perform an initial fill of the data table
adapter.Fill(dataSet, "currency_limits");
DataTable dataTable = dataSet.Tables["currency_limits"];
// Display the results of the initial fill
WriteTable(dataTable);
// Accept the changes made to the data table by the delta
dataTable.AcceptChanges();
// Use the Upsert LoadOption to determine the changes made by the delta
adapter.FillLoadOption = LoadOption.Upsert;
while (WaitHandle.WaitOne())
{
// Stop when connection to the database is lost
if (connection.State == ConnectionState.Closed)
{
break;
}
// Apply the delta to the data table
adapter.FillDelta(dataTable);
// Display the results of the delta
WriteTable(dataTable);
// Accept the changes made to the data table by the delta
dataTable.AcceptChanges();
}
connection.Close();
}
private void ChangeData(DataTable dataTable, PolyActiveDataAdapter adapter)
{
Console.WriteLine("Start update through active query");
// Apply changes to the data table in a single transaction
PolyTransaction transaction;
try
{
transaction = adapter.SelectCommand.Connection.BeginTransaction();
adapter.SelectCommand.Transaction = transaction;
}
catch (Exception e)
{
Console.WriteLine("BeginTransaction failure");
WriteException(e);
return;
}
foreach (DataRow dataRow in dataTable.Rows)
{
double usdollar_starting = (double)dataRow["usdollar_starting"];
string code = (string)dataRow["code"];
double usdollar = (double)dataRow["usdollar"];
double change = (double)dataRow["change"];
// Work out the change we want to make
if (change == 0)
{
usdollar_starting = usdollar;
change = usdollar * 0.01;
dataRow["usdollar_starting"] = usdollar_starting;
}
if (change > 0)
{
if (usdollar + change > usdollar_starting * 1.1)
{
Console.WriteLine("Upper limit crossed");
change = -change;
}
}
else
{
if (usdollar + change <= usdollar_starting * 0.9)
{
Console.WriteLine("Lower limit crossed");
change = -change;
}
}
usdollar += change;
Console.WriteLine("Change usdollar field of {0} by {1:F6} to {2:F6}", code, change, usdollar);
dataRow["usdollar"] = usdollar;
dataRow["change"] = change;
}
// If the table is not empty, commit the changes we have just set up
if (dataTable.Rows.Count > 0)
{
try
{
adapter.Update(dataTable);
transaction.Commit();
Console.WriteLine("Transaction complete");
}
catch (Exception e)
{
Console.WriteLine("Commit failure");
WriteException(e);
}
}
}
private void Run(string[] args)
{
string service = "8001";
bool ftEnable = false;
// Check the correct number of arguments have been supplied
if (args.Length > 2)
{
Console.WriteLine("usage: {0} [<data service> [FT]]", System.AppDomain.CurrentDomain.FriendlyName);
return;
}
// Check whether a service argument has been supplied
if (args.Length >= 1)
{
service = args[0];
}
// Check wether an FT argument has been supplied
if (args.Length >= 2)
{
ftEnable = args[1].Equals("FT");
}
// Build a connection string and connect to the database
PolyConnectionStringBuilder builder = new PolyConnectionStringBuilder();
builder.Service = service;
// Set FT connection settings
builder.FTEnable = ftEnable;
builder.FTHeartbeatInterval = 1000;
builder.FTHeartbeatTimeout = 1000;
builder.FTReconnectionCount = 1000;
builder.FTReconnectionInterval = 1000;
builder.FTReconnectionTimeout = 1000;
PolyConnection connection = new PolyConnection(builder.ConnectionString);
// Register for state change events on the connection
// This is used to detect loss of connection to the database
connection.StateChange += OnStateChange;
// Register for FT mode change events on the connection
connection.FTModeChange += OnFTModeChange;
Console.WriteLine("Connecting to {0}{1}...", service, ftEnable ? " Fault Tolerant" : "");
try
{
connection.Open();
}
catch (Exception)
{
Console.WriteLine("Failed to connect to database");
return;
}
Console.WriteLine("Connection made successfully.");
// Create an active data adapter to perform the active query
PolyActiveDataAdapter adapter = new PolyActiveDataAdapter("select code,usdollar from currency", connection);
// Primary key information must be added to the data table
adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;
// Create a data table to hold the result
DataSet dataSet = new DataSet();
DataTable dataTable = dataSet.Tables.Add("currency");
// Add a column to record the starting usdollar value
DataColumn dataColumn = dataTable.Columns.Add("usdollar_starting", typeof(double));
dataColumn.DefaultValue = 0.0;
// Add a column to record the last change made to the currency
dataColumn = dataTable.Columns.Add("change", typeof(double));
dataColumn.DefaultValue = 0.0;
// Perform an initial fill of the data table
adapter.Fill(dataSet, "currency");
// Change the results of the initial fill
ChangeData(dataTable, adapter);
// Register for data change events
// This indicates when a delta is available for the active query
adapter.DataChange += OnDataChange;
while (true)
{
if (WaitHandle.WaitOne(2000))
{
// Stop when connection to the database is lost
if (connection.State == ConnectionState.Closed)
{
break;
}
// Apply the delta to the data table
adapter.FillDelta(dataTable);
}
else
{
ChangeData(dataTable, adapter);
}
}
connection.Close();
}
