nhibernate "join" - collections

Question

is any way to optimize this solution?
whether there is any possibility of obtaining the same result by calling single query?
public List<Company> GetCompanies(DateTime maxDate, int stockQuotesCount)
{
List<Company> result = new List<Company>();
IList<Company> company = null;
DateTime lastSessionDate = new StockQuoteRepository().GetLastSessionDate(maxDate);
using (ISession s = DataAccessFacade.OpenSesion())
{
String sqlQuery = string.Empty;
sqlQuery = #"Select
*
From
dbo.Company c
Where
c.Company_FirstQuotationDate <= :date and
(c.Company_LastQuotationDate >= :date or c.Company_LastQuotationDate is Null)
Order By
c.Company_Name asc";
company = s.CreateSQLQuery(sqlQuery)
.AddEntity(typeof(Company))
.SetDateTime("date", lastSessionDate)
.List<Company>();
if (company != null)
{
for (int i = 0; i < company.Count; i++)
{
sqlQuery = #"Select
Top(:top)
*
From
dbo.StockQuote sq
Where
sq.StockQuote_Company_Id = :cId
and sq.StockQuote_Date <= :date
Order By
sq.StockQuote_Date desc";
company[i].StockQuotes = s.CreateSQLQuery(sqlQuery)
.AddEntity(typeof(StockQuote))
.SetParameter<int>("cId", company[i].Id)
.SetParameter<int>("top", stockQuotesCount)
.SetDateTime("date", lastSessionDate)
.List<StockQuote>();
}
}
}
return (List<Company>)company;
}
my fluent mapings:
public class CompanyMap : ClassMap<Company>
{
public CompanyMap()
{
this.Id(x => x.Id).Column("Company_Id");
this.Map(x => x.Name).Column("Company_Name");
this.Map(x => x.FirstQuotationDate).Column("Company_FirstQuotationDate");
this.Map(x => x.LastQuotationDate).Column("Company_LastQuotationDate");
this.HasMany(x => x.StockQuotes)
.Cascade.All()
.BatchSize(50)
.Inverse();
}
}
public class StockQuoteMap : ClassMap<StockQuote>
{
public StockQuoteMap()
{
this.Id(x => x.Id).Column("StockQuote_Id");
this.Map(x => x.Open).Column("StockQuote_Open");
this.Map(x => x.Low).Column("StockQuote_Low");
this.Map(x => x.High).Column("StockQuote_High");
this.Map(x => x.Close).Column("StockQuote_Close");
this.Map(x => x.Volume).Column("StockQuote_Volume");
this.Map(x => x.Date).Column("StockQuote_Date");
this.References(x => x.Company).Column("Company_Id");
}
}

Answer 1

ok, it is better query
using (ISession s = DataAccessFacade.OpenSesion())
{
String cHql = #"select
distinct c
from
Company c
join fetch c.StockQuotes s
where
c.FirstQuotationDate <= :maxDate and
(c.LastQuotationDate >= :maxDate or c.LastQuotationDate is Null)
and s.Date >= :minDate
order by
c.Name asc,
s.Date desc";
result = s.CreateQuery(cHql)
.SetDateTime("maxDate", lastSessionDate)
.SetDateTime("minDate", lastSessionDate.AddMonths(-2))
.List<Company>().ToList();
}
but there is one problem,
instead of giving time period for selecting StockQuote by StockQuote.Date form Company.StockQuotes, wants to make the TOP() on this joined collection
really, I only know maxDate (in this case), the calculation minDate is very difficult