public Dictionary<string, Dictionary<object, SourceSignalAttributeMapBean>> BuildSignalMap(String sourceType)
{
String sql = string.Format("SELECT * FROM {0} WHERE {1} = ? ORDER BY {2} ",
SourceSignalMapBean._TABLE_NAME,
SourceSignalMapBean._SOURCE_TYPE,
SourceSignalMapBean._SOURCE_NAME );
OleDbParameter[] dbParams = { CreateParameter(SourceSignalMapBean._SOURCE_TYPE, sourceType)};
List<SourceSignalMapBean> list = CreateList<SourceSignalMapBean>(sql, dbParams);
return list.ToDictionary( sourceSignalMapBean
=> sourceSignalMapBean.sourceName, sourceSignalMapBean
=> BuildSignalAttributeMap( sourceSignalMapBean.id ) );
}