void SetInitialCache()
{
//open default database and subscribe for table update events (update, delete and insert) by setting flag ClientSide.CAsyncDBHandler.ENABLE_TABLE_UPDATE_MESSAGES
bool ok = m_hander.GetCachedTables(DefaultDBName, (res, errMsg) =>
{
uint port;
string ip = m_hander.Socket.GetPeerName(out port);
ip += ":";
ip += port;
m_cache.Set(ip, m_hander.DBManagementSystem);
m_cache.DBServerName = m_hander.Socket.ConnectionContext.Host;
if (res == 0)
{
m_MasterCache.Swap(m_cache); //exchange between master Cache and this m_cache
m_cache.Set(ip, m_hander.DBManagementSystem);
}
}, (vData) =>
{
m_cache.AddRows(m_meta[0].DBPath, m_meta[0].TablePath, vData);
}, (meta) =>
{
m_cache.AddEmptyRowset(meta);
m_meta = meta;
}, UDB.DB_CONSTS.ENABLE_TABLE_UPDATE_MESSAGES);
}
public bool SendMeta(UDB.CDBColumnInfoArray meta, ulong index)
{
//A client expects a rowset meta data and call index
uint ret = SendResult(UDB.DB_CONSTS.idRowsetHeader, meta, index);
return(ret != REQUEST_CANCELED && ret != SOCKET_NOT_FOUND);
}
void SetInitialCache()
{
//open default database and subscribe for table update events (update, delete and insert) by setting flag ClientSide.CAsyncDBHandler.ENABLE_TABLE_UPDATE_MESSAGES
bool ok = m_hander.Open(DefaultDBName, (h, res, errMsg) =>
{
m_cache.Updater = "";
m_cache.Empty();
uint port;
string ip = h.Socket.GetPeerName(out port);
ip += ":";
ip += port;
m_cache.DBServerName = h.Socket.ConnectionContext.Host;
m_cache.Set(ip, h.DBManagementSystem);
}, UDB.DB_CONSTS.ENABLE_TABLE_UPDATE_MESSAGES);
//bring all cached table data into m_cache first for initial cache, and exchange it with Cache if there is no error
ok = m_hander.Execute("", (h, res, errMsg, affected, fail_ok, id) =>
{
if (res == 0)
{
m_MasterCache.Swap(m_cache); //exchange between master Cache and this m_cache
}
}, (h, vData) =>
{
UDB.CDBColumnInfoArray meta = h.ColumnInfo;
try
{
m_cache.AddRows(meta[0].DBPath, meta[0].TablePath, vData);
}
catch (Exception err)
{
Console.WriteLine(err.Message);
}
}, (h) =>
{
try
{
m_cache.AddEmptyRowset(h.ColumnInfo);
}
catch (Exception err)
{
Console.WriteLine(err.Message);
}
});
}
/// <summary>
/// Add an empty rowset from a given column meta data for cache
/// </summary>
/// <param name="meta">A meta data for a rowset</param>
/// <remarks>Track the event that a new rowset is added into a cache by overriding this method</remarks>
public virtual void AddEmptyRowset(UDB.CDBColumnInfoArray meta)
{
if (meta == null || meta.Count == 0)
{
return;
}
if (meta[0].DBPath == null || meta[0].DBPath.Length == 0 || meta[0].TablePath == null || meta[0].TablePath.Length == 0)
{
throw new Exception("The first column meta must contain database name and table name");
}
System.Data.DataTable tbl = ClientSide.CAsyncDBHandler.MakeDataTable(meta, meta[0].TablePath);
if (tbl.PrimaryKey == null || tbl.PrimaryKey.Length == 0)
{
throw new Exception("Column meta must contain at least one key");
}
lock (m_cs)
{
tbl.CaseSensitive = m_bDataCaseSensitive;
m_ds.Add(new KeyValuePair <string, System.Data.DataTable>(meta[0].DBPath, tbl));
}
}
