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copied!<p>Yes, you can use Entity Framework 4 and LINQ on top, it generates the parametrized query and executes it, that's the option.</p> <p>Another option is (and I did several times) to create a base class/interface, let's say:</p> <pre><code>public interface IExecutable { void Execute(IConnection connection); } public interface IExecutable<TResult> : IExecutable { TResult Result { get; } } public abstract ActionBase<TResult> : IExecutable<TResult> { protected void AddParameter(....); protected IDataReader ExecuteAsReader(string query) { //create a DB Command, open transaction if needed, execute query, return a reader. } protected object ExecuteAsScalar(string query) { //.... } //the concrete implementation protected abstract TResult ExecuteInternal(); IExecutable.Execute(IConnection connection) { //keep the connection this.Result = ExecuteInternal(); } //another common logic: } </code></pre> <p>Then you can create your concrete actions:</p> <pre><code>public sealed class GetUsersAction : ActionBase<<IList<User>> { //just a constructor, you provide it with all the information it neads //to be able to generate a correct SQL for this specific situation public GetUsersAction(int departmentId) { AddParameter("@depId", departmentId); } protected override IList<User> ExecuteInternal() { var command = GenerateYourSqlCommand(); using(var reader = ExecuteAsReader(command)) { while(reader.Read) { //create your users from reader } } //return users you have created } } </code></pre> <p>Very easy to create concrete actions!</p> <p>Then, to make it even easier, create an ExecutionManager whose concern is how to get the connection and execute the action:</p> <pre><code>public sealed ExecutionManager() { TResult Execute<TResult>(IExecutable<TResult> action) { var connection = OhOnlyIKnowHowTOGetTheConnectionAnfHereItIs(); action.Execute(connection); return action.Result; } } </code></pre> <p>Now just use it:</p> <pre><code>var getUsersAction = new GetUsersAction(salesDepartmentId); //it is not necessary to be a singletone, up to you var users = ExecutionManager.Instance.Execute(getUsersAction); //OR, if you think it is not up to ExecutionManager to know about the results: ExecutionManager.Instance.Execute(getUsersAction); var users = getUsersAction.Result </code></pre> <p>Using this simple technique it is really easy to move all the connection/command/execution logic away from the concrete actions into the base class, and the concrete actions' concerns are just generating SQLs and converting database output into some meaningful results.</p> <p>Good luck :)</p>

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