fluent nhibernate mapping issue - nhibernate

Question

I have two objects Customer_policy and policy_maturity.
public class Customer_policy
{
public virtual String policy_no { get; set; }
public virtual DateTime maturity_date { get; set; }
public virtual Boolean matured_status { get; set; }
}
public class Policy_maturity
{
public virtual string policy_no { get; set; }
public virtual string customer_id { get; set; }
public virtual float maturity_amt { get; set; }
public virtual string policy_type { get; set; }
public virtual DateTime pay_date { get; set; }
}
When a customer creates a policy Customer_policy is getting populated but Policy_maturity should remain empty(which I have already done). When a policy matures I want to insert a row in Policy_maturity and update matured_status field of the corresponding Customer_policy. What type of mapping should I do so that inserting and update gets accomplished by hitting the database only one time ??? Thanx for your suggestions.

Answer 1

a suggestion:
public class CustomerPolicy
{
public virtual String PolicyNumber { get; private set; }
public virtual DateTime MaturityDate { get; set; }
public virtual PolicyMaturity Maturity { get; private set; }
public virtual Boolean HasMatured { get { return Maturity != null; } }
public virtual void DoMature(Customer customer, float maturity_amt, string policyType, DateTime payDate)
{
DoMature(new PolicyMaturity
{
Customer = customer,
MaturityAmt = maturity_amt,
PolicyType = policyType,
PayDate = payDate,
});
}
/*public*/ virtual void DoMature(PolicyMaturity maturity)
{
Maturity = maturity;
MaturityDate = DateTime.Today;
}
}
public class PolicyMaturity
{
public virtual String PolicyNumber { get; private set; }
public virtual CustomerPolicy Policy { get; set; }
public virtual Customer Customer { get; set; }
public virtual float MaturityAmt { get; set; }
public virtual string PolicyType { get; set; }
public virtual DateTime PayDate { get; set; }
}
class CustomerPolicyMap : ClassMap<CustomerPolicy>
{
public CustomerPolicyMap()
{
Id(cp => cp.PolicyNumber).GeneratedBy.Assigned();
Map(cp => cp.MaturityDate);
HasOne(cp => cp.Maturity);
}
}
class PolicyMaturityMap : ClassMap<PolicyMaturity>
{
public PolicyMaturityMap()
{
Id(cp => cp.PolicyNumber).GeneratedBy.Foreign("Policy");
HasOne(cp => cp.Policy);
References(cp => cp.Customer);
Map(cp => cp.MaturityAmt);
Map(cp => cp.PayDate);
Map(cp => cp.PolicyType);
}
}
then if you save the Updated Customerpolicy NHibernate should batch the two updates

Answer 2

You will need to ask NHibernate to batch the two DML queries. Have a look at this blog post for a detailed description of how to use batching in NHibernate.
Wrapping the two operations in a transaction (as the example in the blog post does) is also a good idea.