public IEnumerator <TModel> GetEnumerator()
{
var queryStrategy = _queryStrategyProvider.GetSelectStrategy(
_queryTable.ModelStrategy, _skipCount, _takeCount, _whereClauses, _orderbyClauses);
var sql = queryStrategy.GetDbQueryScript();
var dbparams = queryStrategy.GetDbParameters();
IDataReader reader = null;
var items = new List <TModel>();
_serviceProvider.Open();
try
{
reader = _serviceProvider.QueryGetReader(sql, dbparams);
if (_skipCount == 0 && _takeCount == 0)
{
var records = DbModelBindingHelper.GetDataRecords(reader);
items.AddRange(
records.Select(record =>
DbModelBindingHelper.BindingRecordToModel <TModel>(
record, _queryTable.ModelStrategy.PropertyStrategies))
);
}
else
{
while (reader.Read())
{
items.Add(DbModelBindingHelper.BindingRecordToModel <TModel>(
reader,
_queryTable.ModelStrategy.PropertyStrategies));
}
}
}
catch (Exception exception)
{
throw new DbOperationException("ERROR_SQL_EXECUTION_FAILED", exception, sql, dbparams);
}
finally
{
reader?.Close();
_serviceProvider.Close();
}
return(items.GetEnumerator());
}
private TModel GetDataModelByPosition(QueryItemPosition position, long dataIndex = 0)
{
var queryStrategy = _queryStrategyProvider.GetSelectStrategy(
_queryTable.ModelStrategy, _skipCount, _takeCount, _whereClauses, _orderbyClauses);
var sql = queryStrategy.GetDbQueryScript();
var dbparams = queryStrategy.GetDbParameters().ToList();
IDataReader reader = null;
TModel model = null;
var singleError = false;
_serviceProvider.Open();
try
{
reader = _serviceProvider.QueryGetReader(sql, dbparams);
var dataAvailable = false;
IDataRecord record = null;
var idx = 0;
switch (position)
{
case QueryItemPosition.Single:
while (reader.Read())
{
if (dataAvailable)
{
break;
}
if (idx > 1)
{
singleError = true;
break;
}
idx++;
dataAvailable = true;
model = DbModelBindingHelper.BindingRecordToModel <TModel>(
reader,
_queryTable.ModelStrategy.PropertyStrategies);
}
break;
case QueryItemPosition.ElementAt:
idx = -1;
while (reader.Read())
{
idx++;
if (idx == dataIndex)
{
record = reader;
model = DbModelBindingHelper.BindingRecordToModel <TModel>(
record, _queryTable.ModelStrategy.PropertyStrategies);
break;
}
}
break;
case QueryItemPosition.First:
reader.Read();
record = reader;
model = DbModelBindingHelper.BindingRecordToModel <TModel>(
record, _queryTable.ModelStrategy.PropertyStrategies);
break;
case QueryItemPosition.Last:
while (reader.Read())
{
record = reader;
model = DbModelBindingHelper.BindingRecordToModel <TModel>(
record, _queryTable.ModelStrategy.PropertyStrategies);
}
break;
default:
throw new NotSupportedException();
}
}
catch (Exception exception)
{
throw new DbOperationException("ERROR_SQL_EXECUTION_FAILED", exception, sql, dbparams);
}
finally
{
reader?.Close();
_serviceProvider.Close();
}
if (singleError)
{
throw new InvalidOperationException("ERROR_OUT_OF_SINGLE_RECORD");
}
return(model);
}