Question

I am trying to insert multiple records into a table where each record has a sequence number that relies on the sequence number of a previously inserted record.

For example:

var db = new StoreDataContext();
var inserts = payments.Select(p => new payment 
{
    order_fk = p.order_fk, line_no = DbMethods.GetNextLine(p.order_fk), 
    amount = p.amount
});

db.payments.InsertAllOnSubmit(inserts);
db.SubmitChanges(ConflictMode.FailOnFirstConflict);

DbMethods.GetNextLine is a SQL scalar function that goes and gets the MAX(line_no) + 1 for that particular order.

My problem is that the function gets performed before the actual inserts happen, so all of the values for line_no are the same. Is there anyway of doing this without submitting each record seperately?

Answer 1

The only way I know to do something like this with Linq to SQL is to wrap it in a transaction.

var db = new StoreDataContext();
using(var scope = new TransactionScope()){        
    foreach(var p in payments){
        db.payments.Insert(new payment 
                          {    order_fk = p.order_fk, 
                               line_no = DbMethods.GetNextLine(p.order_fk),     
                                amount = p.amount
                          });
        db.SubmitChanges(ConflictMode.FailOnFirstConflict);
    }
    scope.Complete();
}