// basic methods
// get
public String GetString(String key)
{
String value = null;
using (SqlConnection sqlConnection = DB.NewSqlConnection()) {
String cmdText = @"SELECT value FROM " + TableName + " WHERE name = " + QCDBClient.EscapeString(key);
SqlCommand sqlCommand = new SqlCommand(cmdText, sqlConnection);
sqlConnection.Open();
Object r = sqlCommand.ExecuteScalar();
if (r != null)
{
value = r.ToString();
}
sqlConnection.Close();
}
return(value);
}
public StreamingEventSource()
{
DB = InitDB();
Options = InitStreamingOptions();
DB.CreateTable(TableName, ValueDefs);
SqlConnection = DB.NewSqlConnection();
SqlConnection.Open();
// init the cursor and options
String dropCursorCmd = String.Format(@"DEALLOCATE {0};", CursorName);
String createCursorCmd = String.Format(@"DECLARE {0} CURSOR Dynamic Read_Only
FOR SELECT * FROM {1} where row_id>={2}
OPEN {0};", CursorName, TableName, Options.CurrentRow);
DB.ExecuteNonQuery(createCursorCmd, SqlConnection);
FetchNextCursorCmd = String.Format(@"FETCH NEXT FROM {0};", CursorName);
FetchPriorCursorCmd = String.Format(@"FETCH PRIOR FROM {0};", CursorName);
FetchScrollCursorCmd = String.Format(@"FETCH ABSOLUTE {0} FROM {1};", Options.CurrentRow, CursorName);
ValueNames = ValueDefs.ToList()
.Select(def => def.ColumnName).ToArray();
// skip to the unhappend event
//while (true)
//{
Object[] rs = NextRow();
if (rs != null)
{
if (IsValidRow(rs))
{
//back one
PriroRow();
//break;
}
//else continue; // visited rows
}
// else break;
//}
}