In LINQ-SQL, wrap the DataContext is an using statement - pros cons

Question

Can someone pitch in their opinion about pros/cons between wrapping the DataContext in an using statement or not in LINQ-SQL in terms of factors as performance, memory usage, ea

Answer 1

I depends on the complexity of your Data Layer. If every call is a simple single query, then each call can be wrapped in the Using like in your question and that would be fine.

If, on the other hand, your Data Layer can expect multiple sequential calls from the Business Layer, the you'd wind up repeatedly creating/disposing the DataContext for each larger sequence of calls. not ideal.

What I've done is to create my Data Layer object as IDisposible. When it's created, the DataContext is created (or really, once the first call to a method is made), and when the Data Layer object disposes, it closes and disposes the DataContext.

here's what it looks like:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Configuration;

namespace PersonnelDL
{
    public class PersonnelData : IDisposable
    {
        #region DataContext management
        /// 

        /// Create common datacontext for all data routines to the DB
        /// 
        private PersonnelDBDataContext _data = null;
        private PersonnelDBDataContext Data
        {
            get
            {
                if (_data == null)
                {
                    _data = new PersonnelDBDataContext(ConfigurationManager.ConnectionStrings["PersonnelDB"].ToString());
                    _data.DeferredLoadingEnabled = false; // no lazy loading
                    //var dlo = new DataLoadOptions(); // dataload options go here
                }
                return _data;
            }
        }

        /// 

        /// close out data context
        /// 
        public void Dispose()
        {
            if (_data != null)
                _data.Dispose();
        }
        #endregion

        #region DL methods
        public Person GetPersonByID(string userid)
        {
            return Data.Persons.FirstOrDefault(p => p.UserID.ToUpper().Equals(userid.ToUpper()));
        }

        public List GetPersonsByIDlist(List useridlist)
        {
            var ulist = useridlist.Select(u => u.ToUpper().Trim()).ToList();
            return Data.Persons.Where(p => ulist.Contains(p.UserID.ToUpper())).ToList();
        }

        // more methods...
        #endregion
    }
}