• 0

[ASP.NET, Design] Business Logic Layer or Stored procedures?


Question

Hello,

I'm trying to see which route is best. Having a Business Logic Layer or have all the logic as stored procedures in the database.

The application architecture looks like this: Data Access Layer (LINQ to SQL) -> Business Logic Layer (Needed?) -> UI Layer (Web).

Does it make sense to have the middle layer if everything is done via stored procedures? If not, what do you recommend for the BLL? Could you advice on both routes? Advantages and disadvantages? Kindly note that the application is married to the database (Sql Server 2005) so there is no need to take into concideration that the dbms will change in the future.

Thanks.

14 answers to this question

Recommended Posts

  • 0

I generally stick to the 3-layer architecture for my (admittedly quite small) ASP.NET systems. The business logic layer (even with stored procedures) allows you to add exception handling and more advanced input validation to your system between the presentation layer and the linq-to-sql layer, and for that I would recommend keeping it.

  • 0

Thanks for your input. What kind of class naming do you recommend for this layer? The DAC layer already has the entity objects (like Item, Subject).

  On 25/01/2010 at 08:21, Majesticmerc said:

I generally stick to the 3-layer architecture for my (admittedly quite small) ASP.NET systems. The business logic layer (even with stored procedures) allows you to add exception handling and more advanced input validation to your system between the presentation layer and the linq-to-sql layer, and for that I would recommend keeping it.

  • 0

I always use both

1) Presentation layer

2) Business layer (most of the time i still use ado.net though) that calls stored procedures

3) Stored procedures that contains most of the transactional stuff

4) Database with foreign keys for data integrity

  • 0

One thing I cannot understand is why some developers have a layer which talks to the db using one entity type and then converts to another so the main application can then use it......all your doing is adding more for to your already long list of things to do! Designing a database properly will combat this. So you can in a sense merge one the entity layer and business logic layer into one.

Have a look at this: http://www.west-wind.com/WebLog/posts/160237.aspx

The code files are here: http://www.west-wind.com/files/conferences/conn_LinqToSqlBusiness.zip

Basically it's a DataContext lifetime management and factory wrapper class.

How to use it:

Create a new Project, create two folders with the project called "BusinessFramework" and "BusinessObjects". Grab the "wwDataContext.cs" and "wwBusinessObject.cs" files and put them into the "BusinessFramework" folder. I rename them to "<shortprojectname>BusinessObject.cs" and "<shortProjectName>BusinessDataContext" but rename them as you see fit.

Create a DBML file (called YourData, which then becomes YourDataDataContext) in the "BusinessFramework" folder, right click WITHIN the DBML, select Properties. Under "Base Class" set to "<shortProjectName>BusinessDataContext", Under Connection set "Application Settings" to False, "Connection String" to None.

Right click on the DBML select "View Code".

You *may* need to change the namespace on this class first, it'll depend. it should be the full namespace of where the file is..... eg:

someNamespace.projectName.Data.BusinessFramework

rather than

someNamespace.projectName.Data

it should look something like this:

    public partial class DBMLNameDataContext         
    {

        public DBMLNameDataContext()
            : base(ConfigurationManager.ConnectionStrings["YourConnectionStringNameFromApp.Config"].ConnectionString, new AttributeMappingSource())
        {
            OnCreated();
        }

    }

Create an app.config file within the root of the Project. Add a new Connection String, putting the correct name into the class above.

Add a table into the DBML.....this will be signified by <entityName>

Create a new class file (within "BusinessObjects" folder) called "Bus<entityName>.cs", we have here tbl_Engineer which is named "Engineer" in the DBML, so the file becomes "BusEngineer.cs".

public class BusEngineers : &lt;shortprojectname&gt;BusinessObject&lt;tbl_engineer, YourDataDataContext&gt;
    {
    }

Within the root of the Project create a new class file called "<shortProjectName>DataFactory.cs", within this add:

        public static BusEngineers GetEngineers
        {
            get
            {
                return new BusEngineers();
           }
        }

So to use the whole Data Layer....in another project add:

<shortProjectName>DataFactory.GetEngineers. => this will then list all your public methods within your BusEngineer class.

You could even move all the Business Objects out into another project if you needed to.

Done - I think.....any questions feel free to PM me.

GE

  • 0

Thanks a lot, I'll look into that :).

  On 25/01/2010 at 11:04, garethevans1986 said:

One thing I cannot understand is why some developers have a layer which talks to the db using one entity type and then converts to another so the main application can then use it......all your doing is adding more for to your already long list of things to do! Designing a database properly will combat this. So you can in a sense merge one the entity layer and business logic layer into one.

Have a look at this: http://www.west-wind...sts/160237.aspx

The code files are here: http://www.west-wind...SqlBusiness.zip

Basically it's a DataContext lifetime management and factory wrapper class.

How to use it:

Create a new Project, create two folders with the project called "BusinessFramework" and "BusinessObjects". Grab the "wwDataContext.cs" and "wwBusinessObject.cs" files and put them into the "BusinessFramework" folder. I rename them to "<shortprojectname>BusinessObject.cs" and "<shortProjectName>BusinessDataContext" but rename them as you see fit.

Create a DBML file (called YourData, which then becomes YourDataDataContext) in the "BusinessFramework" folder, right click WITHIN the DBML, select Properties. Under "Base Class" set to "<shortProjectName>BusinessDataContext", Under Connection set "Application Settings" to False, "Connection String" to None.

Right click on the DBML select "View Code".

You *may* need to change the namespace on this class first, it'll depend. it should be the full namespace of where the file is..... eg:

someNamespace.projectName.Data.BusinessFramework

rather than

someNamespace.projectName.Data

it should look something like this:

 public partial class DBMLNameDataContext 
 {

 public DBMLNameDataContext()
 : base(ConfigurationManager.ConnectionStrings["YourConnectionStringNameFromApp.Config"].ConnectionString, new AttributeMappingSource())
 {
 OnCreated();
 }

 }

Create an app.config file within the root of the Project. Add a new Connection String, putting the correct name into the class above.

Add a table into the DBML.....this will be signified by <entityName>

Create a new class file (within "BusinessObjects" folder) called "Bus<entityName>.cs", we have here tbl_Engineer which is named "Engineer" in the DBML, so the file becomes "BusEngineer.cs".

public class BusEngineers : &lt;shortprojectname&gt;BusinessObject&lt;tbl_engineer, YourDataDataContext&gt;
 {
 }

Within the root of the Project create a new class file called "<shortProjectName>DataFactory.cs", within this add:

 public static BusEngineers GetEngineers
 {
 get
 {
 return new BusEngineers();
 }
 }

So to use the whole Data Layer....in another project add:

<shortProjectName>DataFactory.GetEngineers. => this will then list all your public methods within your BusEngineer class.

You could even move all the Business Objects out into another project if you needed to.

Done - I think.....any questions feel free to PM me.

GE

  • 0

Yeah I should probably mention too that I work mostly in ADO.NET, where business logic layers are pretty standard, so the method that Gareth mentioned might be more suited for you, although only you can make that decision :)

  • 0

A correction to the above post....because of this:

https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=361577&wa=wsignin1.0

namespace CompanyName.ProjectName.Data.BusinessFramework
{

    // DO NOT REMOVE
    using System.Configuration;
    using System.Data.Linq.Mapping;
    // SEE HERE - https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=361577&wa=wsignin1.0
    // GE, 26/01/10

    public partial class DBMLNameDataContext
    {


        public DBMLNameDataContext()
            : base(ConfigurationManager.ConnectionStrings["YourConnectionStringNameFromApp.Config"].ConnectionString, new AttributeMappingSource())
        {
            OnCreated();
        }

    }
}

  • 0

I rarely use stored procedures anymore. I used to use them religiously. I had one for every function in the system. Looking back now I wonder what I was thinking. What a waste that was.

In most of my applications, I typically use an architecture that many people call the Onion Architecture. I design my apps so that they're testable (automated testing, not F5 testing) because it's important to me.

I'll have a bunch a repository classes that interface with my database via nhibernate, domain classes and service layer classes, when they're required. Outside of those, I'll have presentation model classes for strongly-typed views.

  • 0
  On 26/01/2010 at 15:59, sbauer said:

I rarely use stored procedures anymore. I used to use them religiously. I had one for every function in the system. Looking back now I wonder what I was thinking. What a waste that was.

In most of my applications, I typically use an architecture that many people call the Onion Architecture. I design my apps so that they're testable (automated testing, not F5 testing) because it's important to me.

I'll have a bunch a repository classes that interface with my database via nhibernate, domain classes and service layer classes, when they're required. Outside of those, I'll have presentation model classes for strongly-typed views.

Looks like a nice article, gonna give that a read. Cheers!

I must admit that I used to use Stored Procedures for ALL my SQL, and to be honest, it did little to nothing to help the structure of my systems. Now (since I'm fortunate enough to develop in ASP.NET (no MVC yet though which is a bummer)) I tend to take advantage of the ADO.NET dataset designer to handle all my SQL statements, which makes life much easier since I can manage the entire system from inside Visual Studio.

  • 0
  Quote

I rarely use stored procedures anymore. I used to use them religiously. I had one for every function in the system. Looking back now I wonder what I was thinking. What a waste that was.

Could you tell us why it was a waste? I'm interested in knowing.

  • 0
  On 26/01/2010 at 23:58, Majesticmerc said:

Looks like a nice article, gonna give that a read. Cheers!

I must admit that I used to use Stored Procedures for ALL my SQL, and to be honest, it did little to nothing to help the structure of my systems. Now (since I'm fortunate enough to develop in ASP.NET (no MVC yet though which is a bummer)) I tend to take advantage of the ADO.NET dataset designer to handle all my SQL statements, which makes life much easier since I can manage the entire system from inside Visual Studio.

Stored procedures are such a fun topic because many people love them. I did too. I loved how my code looked. I loved how I had SQL sitting in the database, not in my code. Eventually, though, I got tired of it like you. I don't use ADO.NET dataset designer because I don't feel it scales well to larger systems and starts to break down.

It's unfortunate that you can't use MVC. If I never work in a WebForms project again, I'll be happy.

  On 27/01/2010 at 07:35, Ali Koubeissi said:

Could you tell us why it was a waste? I'm interested in knowing.

  On 27/01/2010 at 10:02, garethevans1986 said:

Because your "business logic" should not be in the database...

That's part of the reasoning behind it.

We use unit tests on our projects. Our unit tests ensure that 1) our features work as designed and 2) our features still work even after we've added new features. When you add business logic to stored procedures, you're beyond unit tests now. Unit tests need to be fast, and isolated - a small unit. Testing the database is not quick, and it's not a small unit. You'll need to create integration tests and those will be much slower. When things run slow, people tend not to use them.

Another reason is that I stopped generating most of my SQL by hand. No more CRUD sprocs, or adhoc statements. NHibernate takes care of that for us. If we have a very complicated query that we need to execute and the query looks pretty ugly while using the NHibernate API, then we'll generate the SQL by hand.

So far, so good. We'll have a repository that inherits from a base repository for each entity in the system.

    public abstract class RepositoryWithTypedKey&lt;KEY,ENTITY&gt;: IRepositoryWithTypedKey&lt;KEY,ENTITY&gt; where ENTITY: class 
    {
        protected ISession session;

        protected RepositoryWithTypedKey(ISession session)
        {
            this.session = session;
        }
        public ENTITY Get(KEY id)
        {
            return Session.Get<ENTITY>(id);
        }

        public ENTITY Load(KEY id)
        {
            return Session.Load<ENTITY>(id);
        }

        public IEnumerable&lt;ENTITY&gt; GetAll()
        {
            return Session.CreateCriteria&lt;ENTITY&gt;().List&lt;ENTITY&gt;();
        }

        public void Save(ENTITY entity)
        {
            Session.Save(entity);
        }

        public void Update(ENTITY entity)
        {
            Session.Update(entity);
        }

        public void SaveOrUpdate(ENTITY entity)
        {
            Session.SaveOrUpdate(entity);
        }

        public ISession Session { get { return session; } }
    }

    public class EmployeeRepository: Repository&lt;Employee&gt;, IEmployeeRepository
    {
        public EmployeeRepository(ISession session) : base(session)
        {
        }

        public IList&lt;Employee&gt; SearchByLastName(string lastName)
        {
            var criteria = Session.CreateCriteria&lt;Employee&gt;();
            criteria.Add(Expression.Like("LastName" + lastName + "%"));
            criteria.AddOrder(Order.Asc("LastName            return criteria.List<Employee>;();
        }

    }

And the controller

public class HomeController : Controller
    {
        private readonly IEmployeeRepository _employeeRepository;

        public HomeController(IEmployeeRepository _employeeRepository)
        {
            this._employeeRepository = _employeeRepository;
        }

        [HttpGet]
        public ActionResult Index()
        {
            return View();
        }

        [HttpPost]
        [ActionName("Index")]
        public ActionResult IndexSearch(string search)
        {
            return RedirectToAction("Search", new { searchTerm = search });
        }

        [Transaction]
        public ActionResult Search(string searchTerm)
        {
            if(string.IsNullOrEmpty(searchTerm))
                return RedirectToAction("index");

            var model = new HomeControllerViewModel();
            model.Employees = _employeeRepository.GetEmployeeListByLastName(searchTerm);
            model.Search = searchTerm;
            return View(model);

        }

    }

  • 0

I've come accross NHibernate, Fluent NHibernate and Dependency Injection before.

The only problem I have with NHibernate is how do you script the changes to keep your SQL Servers up to date?

GE

This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Posts

    • Charlie Manson, They must be his devotees.
    • Download Excel Quick and Easy (worth $12) for free by Steven Parker Claim your complimentary eBook worth $12 for free, before the offer ends on June 24. Drawn from the most important tasks in the latest bestselling Excel Bible , Excel Quick and Easy is your ticket to data mastery. Excel veterans Michael Alexander and Dick Kusleika distil the most essential and useful tasks you need to understand about the world's most popular spreadsheet program, from functions to charts, graphs, formulas and more. Prepare for a whirlwind tour of Excel, packed with simple and step-by-step guides to common and lesser-known Excel features. This book shows you how to: Create new spreadsheets and workbooks by entering and editing worksheet data Simplify working with large amounts of data by naming and moving ranges Make calculations and draw conclusions from your data by using formulas Visualize and present your data by creating functional charts The secret weapon in your productivity arsenal Being great at Excel is quickly becoming a standard expectation for a ton of employers and organizations, in all sorts of industries. Sharpening your skills can boost your workplace performance and make it easier to land promotions or find new roles. Excel Quick and Easy makes it a breeze to develop the proficiencies that help you stand out from your peers. Unique features of this book Step-by-step guides to the most commonly used and productive Excel tasks, from basic worksheet operations to formatting spreadsheets for hardcopy printing Intuitive explanations for making your data tell a compelling story with visualizations, including charts, graphs, and tables Advanced number-crunching techniques, including formulas and functions, that help you unlock fresh insights and new conclusions from your data Excel Quick and Easy is the perfect reference for brand-new Excel users trying to get up-to-speed quickly and confidently. It's also a must-read for anyone migrating from another spreadsheet program, like Google Sheets, or more experienced Excel users who need to solidify and improve their skills. If you're tired of stumbling through your spreadsheets and just “surviving” in Excel, grab a copy of Excel Quick and Easy and supercharge your productivity. You'll refine your understanding of the basics, learn brand-new skills and features, and become the Excel expert that every office desperately needs. This free to download offer expires June 24. How to get it Please ensure you read the terms and conditions to claim this offer. Complete and verifiable information is required in order to receive this free offer. If you have previously made use of these free offers, you will not need to re-register. While supplies last! Download Excel Quick and Easy (worth $12) for free Offered by Packt, view other free resources The below offers are also available for free in exchange for your (work) email: AI and Innovation ($21 Value) FREE – Expires 6/11 Unruly: Fighting Back when Politics, AI, and Law Upend [...] ($18 Value) FREE - Expires 6/17 SQL Essentials For Dummies ($10 Value) FREE – Expires 6/17 Continuous Testing, Quality, Security, and Feedback ($27.99 Value) FREE – Expires 6/18 VideoProc Converter AI v7.5 for FREE (worth $78.90) – Expires 6/18 Macxvideo AI ($39.95 Value) Free for a Limited Time – Expires 6/22 Excel Quick and Easy ($12 Value) FREE – Expires 6/24 The Inclusion Equation: Leveraging Data & AI ($21 Value) FREE – Expires 6/24 Microsoft 365 Copilot At Work ($60 Value) FREE – Expires 6/25 Natural Language Processing with Python ($39.99 Value) FREE – Expires 6/25 How to Engage Buyers and Drive Growth in the Age of AI ($22.95 Value) FREE – Expires 7/1 Using Artificial Intelligence to Save the World ($30.00 Value) FREE – Expires 7/1 Essential: How Distributed Teams, Generative AI, [...] ($18.00 Value) FREE – Expires 7/2 The Chief AI Officer's Handbook: Master AI leadership with strategies to innovate, overcome challenges, and drive business growth ($9.99 Value) FREE for a Limited Time – Expires 7/2 The Ultimate Linux Newbie Guide – Featured Free content Python Notes for Professionals – Featured Free content Learn Linux in 5 Days – Featured Free content Quick Reference Guide for Cybersecurity – Featured Free content We post these because we earn commission on each lead so as not to rely solely on advertising, which many of our readers block. It all helps toward paying staff reporters, servers and hosting costs. Other ways to support Neowin The above deal not doing it for you, but still want to help? Check out the links below. Check out our partner software in the Neowin Store Buy a T-shirt at Neowin's Threadsquad Subscribe to Neowin - for $14 a year, or $28 a year for an ad-free experience Disclosure: An account at Neowin Deals is required to participate in any deals powered by our affiliate, StackCommerce. For a full description of StackCommerce's privacy guidelines, go here. Neowin benefits from shared revenue of each sale made through the branded deals site.
    • At least Starship Block 2 is consistent in failure.  They were lucky it was not the stack. That would have been really huge. 
    • VR is dead on the PS at this rate, sales just aren't there. Way more VR push on the PC, even Sony knows this and that's why they added PC support to the PSVR.
  • Recent Achievements

    • First Post
      MikeK13 earned a badge
      First Post
    • One Month Later
      OHI Accounting earned a badge
      One Month Later
    • Week One Done
      OHI Accounting earned a badge
      Week One Done
    • First Post
      Thornskade earned a badge
      First Post
    • Week One Done
      Higante88 earned a badge
      Week One Done
  • Popular Contributors

    1. 1
      +primortal
      716
    2. 2
      ATLien_0
      273
    3. 3
      Michael Scrip
      203
    4. 4
      +FloatingFatMan
      182
    5. 5
      Steven P.
      128
  • Tell a friend

    Love Neowin? Tell a friend!