protected override Expression VisitField(FieldExpression field)
{
var fields = new FieldGatherer().Gather(field.Expression);
if (fields.Count == 0)
_fields.Add(field);
else
_fields.AddRange(fields);
return base.VisitField(field);
}
protected override Expression VisitField(FieldExpression field)
{
var fields = new FieldGatherer().Gather(field.Expression);
if (fields.Count == 0)
{
_fields.Add(field);
}
else
{
_fields.AddRange(fields);
}
return(base.VisitField(field));
}
protected override Expression VisitSelect(SelectExpression select)
{
select = PreProcessSelect(select);
if (select.From != null)
{
VisitSource(select.From);
}
if (select.Where != null)
{
try
{
//try this first, and if it fails, resort to javascript generation, which is slower on the server side.
_queryObject.SetQueryDocument(new BsonDocumentFormatter().FormatDocument(select.Where));
}
catch (Exception ex)
{
_queryObject.SetWhereClause(new JavascriptFormatter().FormatJavascript(select.Where));
}
}
if (_queryAttributes.IsMapReduce)
{
_queryObject.IsMapReduce = true;
_queryObject.MapFunction = new MapReduceMapFunctionBuilder().Build(select.Fields, select.GroupBy);
_queryObject.ReduceFunction = new MapReduceReduceFunctionBuilder().Build(select.Fields);
_queryObject.FinalizerFunction = new MapReduceFinalizerFunctionBuilder().Build(select.Fields);
}
else if (!_queryAttributes.IsCount && !select.Fields.HasSelectAllField())
{
var fieldGatherer = new FieldGatherer();
foreach (var field in select.Fields)
{
var expandedFields = fieldGatherer.Gather(field.Expression);
foreach (var expandedField in expandedFields)
{
_queryObject.Fields[expandedField.Name] = 1;
}
}
}
if (select.OrderBy != null)
{
foreach (var order in select.OrderBy)
{
var field = Visit(order.Expression) as FieldExpression;
if (field == null)
{
throw new InvalidQueryException("Complex order by clauses are not supported.");
}
_queryObject.AddSort(field.Name, order.OrderType == OrderType.Ascending ? 1 : -1);
}
}
if (select.Take != null)
{
_queryObject.NumberToLimit = EvaluateConstant <int>(select.Take);
}
if (select.Skip != null)
{
_queryObject.NumberToSkip = EvaluateConstant <int>(select.Skip);
}
return(select);
}
