Question

I have a table with following columns:

ContractorId ……… INT …………. IDENTITY
ContractorName …….. Varchar(50) ……. P.K
ContractorGrade ……. Varchar(3) ……. P.K

The class generated by PetaPoco T4 template looks like this:

[TableName("contractor_master")]
[PrimaryKey("contractorname", autoIncrement=false)]
[ExplicitColumns]
public partial class contractor_master : TubewellRepo.Record<contractor_master>  
{
    [Column] 
    public int contractorid 
    { 
        get
        {
            return _contractorid;
        }
        set
        {
            _contractorid = value;
            MarkColumnModified("contractorid");
        }
    }
    int _contractorid;

    [Column] 
    public string contractorname 
    { 
        get
        {
            return _contractorname;
        }
        set
        {
            _contractorname = value;
            MarkColumnModified("contractorname");
        }
    }
    string _contractorname;

    [Column] 
    public string contractorgrade 
    { 
        get
        {
            return _contractorgrade;
        }
        set
        {
            _contractorgrade = value;
            MarkColumnModified("contractorgrade");
        }
    }
    string _contractorgrade;
  }

The code to INSERT a new record is as below:

// Insert a record
var Contractor=new contractor_master();
Contractor.contractorname = "Super Borewells";
Contractor.contractorgrade = "A";

db.Insert(Contractor);

In the second line of the Class Code, I want to know how to mention a Composite Key, which is (ContractorName + ContractorGrade).

Secondly, it is not inserting a record because it expects an Id column. Even though ContractorId is IDENTITY, it is not a primary key.

It is not INSERTING a new record and gives error because it is inserting 0 in the IDENTITY column.

Answer 1

My branch here: https://github.com/schotime/petapoco
supports composite primary key by specifying the PrimaryKey attribute like:

[PrimaryKey("ContractorName,ContractorGrade")]

I’m not sure how it will work if you want the identity column there as well.