public TResult Calculate(QueryModel queryModel)
{
var projector = ProjectorBuildingExpressionTreeVisitor <TInput> .BuildProjector(queryModel);
var resultItems = GetData().Select(it => projector(it));
var type = typeof(TInput);
if (typeof(TInput).IsGenericType)
{
type = typeof(TInput).GetGenericArguments()[0];
}
if (type == typeof(decimal))
{
return((TResult)((object)resultItems.Cast <decimal?>().Average()));
}
else if (type == typeof(long))
{
return((TResult)((object)resultItems.Cast <long?>().Average()));
}
else if (type == typeof(int))
{
return((TResult)((object)resultItems.Cast <int?>().Average()));
}
else if (type == typeof(double))
{
return((TResult)((object)resultItems.Cast <double?>().Average()));
}
else if (type == typeof(float))
{
return((TResult)((object)resultItems.Cast <float?>().Average()));
}
throw new NotSupportedException("Unknown type for sum. Supported types: decimal, long, int, double, float");
}
private T ExecuteSum <T>(QueryModel queryModel)
{
var projector = ProjectorBuildingExpressionTreeVisitor <T> .BuildProjector(queryModel);
var resultItems = LoadData(queryModel).Select(it => projector(it));
var type = typeof(T);
if (typeof(T).IsGenericType)
{
type = typeof(T).GetGenericArguments()[0];
}
if (type == typeof(decimal))
{
return((T)((object)resultItems.Cast <decimal?>().Sum()));
}
else if (type == typeof(long))
{
return((T)((object)resultItems.Cast <long?>().Sum()));
}
else if (type == typeof(int))
{
return((T)((object)resultItems.Cast <int?>().Sum()));
}
else if (type == typeof(double))
{
return((T)((object)resultItems.Cast <double?>().Sum()));
}
else if (type == typeof(float))
{
return((T)((object)resultItems.Cast <float?>().Sum()));
}
throw new NotSupportedException("Unknown type for sum. Supported types: decimal, long, int, double, float");
}
private static Func <string, T> ProjectMapping <T>(SubQueryExpression sqe, QueryParts parts, SubqueryParts subquery)
{
Func <string, T> result;
var projector = ProjectorBuildingExpressionTreeVisitor <T> .BuildProjector(sqe.QueryModel);
if (subquery.Selects.Count == 1)
{
var sel = subquery.Selects[0];
var factory = CreateResult(sel.Name, sel.ItemType, sel.QuerySource, parts, true);
result = value => (T)factory.Instancer(value);
}
else
{
var ssd = SelectSubqueryData.Create(parts, subquery);
result = value =>
{
//TODO fix later
return(default(T));
/*
* var items = OracleRecordConverter.ParseRecord(value);
* var rom = ssd.ProcessRow(null, items);
* var res = projector(rom);
* return res;*/
};
}
return(result);
}
private static Func <string, BufferedTextReader, T> ProjectMapping <T>(SubQueryExpression sqe, QueryParts parts, SubqueryParts subquery)
{
Func <string, BufferedTextReader, T> result;
var projector = ProjectorBuildingExpressionTreeVisitor <T> .BuildProjector(sqe.QueryModel);
if (subquery.Selects.Count == 1)
{
var sel = subquery.Selects[0];
var factory = CreateResult(sel.Name, sel.ItemType, sel.QuerySource, parts);
result = (value, reader) => (T)factory.Instancer(value, reader);
}
else
{
var ssd = SelectSubqueryData.Create(parts, subquery);
//TODO TextReader/string !?
result = (value, reader) =>
{
var items = PostgresRecordConverter.ParseRecord(value);
var rom = ssd.ProcessRow(null, reader, items);
var res = projector(rom);
return(res);
};
}
return(result);
}
private T ExecuteSeedAggregate <T>(QueryModel queryModel, AggregateFromSeedResultOperator seedAggregate)
{
var projector = ProjectorBuildingExpressionTreeVisitor <T> .BuildAggregateProjector(queryModel, seedAggregate.Func);
var resultItems = LoadData(queryModel);
var result = seedAggregate.GetConstantSeed <T>();
foreach (var item in resultItems)
{
result = projector(item)(result);
}
return(result);
}
protected Func <object, T> GetSelectProjector <T>(object firstResult, QueryModel queryModel)
{
Func <object, T> projector = result => result.Cast <T>();
if (!ShouldBuildResultObjectMapping <T>(firstResult, queryModel))
{
return(projector);
}
var proj = ProjectorBuildingExpressionTreeVisitor.BuildProjector <T>(queryModel.SelectClause.Selector);
projector = result => proj(new ResultObjectMapping(queryModel.MainFromClause, result));
return(projector);
}
private static Func <string, T> ProjectMapping <T>(SubQueryExpression sqe, QueryParts parts, SubqueryParts subquery)
{
var ssd = SelectSubqueryData.Create(parts, subquery);
var projector = ProjectorBuildingExpressionTreeVisitor <T> .BuildProjector(sqe.QueryModel);
//TODO TextReader/string !?
Func <string, T> result = value =>
{
var items = PostgresRecordConverter.ParseRecord(value);
var rom = ssd.ProcessRow(null, items);
var res = projector(rom);
return(res);
};
return(result);
}
// Executes a query with a collection result.
public IEnumerable <T> ExecuteCollection <T>(QueryModel queryModel)
{
var hasUnion = queryModel.ResultOperators.Any(it => it is UnionResultOperator || it is ConcatResultOperator);
if (hasUnion)
{
queryModel = queryModel.ConvertToSubQuery("sq");
}
var projector = ProjectorBuildingExpressionTreeVisitor <T> .BuildProjector(queryModel);
var resultItems = LoadData(queryModel);
foreach (var item in resultItems)
{
yield return(projector(item));
}
}
private T ExecuteAggregate <T>(QueryModel queryModel, AggregateResultOperator aggregate)
{
var valueProjector = ProjectorBuildingExpressionTreeVisitor <T> .BuildProjector(queryModel);
var funcProjector = ProjectorBuildingExpressionTreeVisitor <T> .BuildAggregateProjector(queryModel, aggregate.Func);
var resultItems = LoadData(queryModel);
if (resultItems.Count == 0)
{
throw new DataException("For aggregate operation at least one result must be used");
}
var result = valueProjector(resultItems[0]);
foreach (var item in resultItems.Skip(1))
{
result = funcProjector(item)(result);
}
return(result);
}
private static Func <string, T> ProjectMapping <T>(SubQueryExpression sqe, QueryParts parts, SubqueryParts subquery)
{
var ssd = SelectSubqueryData.Create(parts, subquery);
var projector = ProjectorBuildingExpressionTreeVisitor <T> .BuildProjector(sqe.QueryModel);
Func <string, T> result = value =>
{
//TODO fix later
return(default(T));
/*
* var items = OracleRecordConverter.ParseRecord(value);
* var rom = ssd.ProcessRow(null, items);
* var res = projector(rom);
* return res;*/
};
return(result);
}
