• 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

    • This 2TB NVMe Gen4 SSD is priced just $94 and you also get a free 64GB UHS-I memory card by Sayan Sen A few days ago, we reported on Team Group's T-FORCE G50 4TB NVMe SSD that was up for grabs at just $200 thanks to a promo coupon. Sadly, that deal has expired although you can still WD's SN8100 (Gen5) and SN7100 (Gen4) offerings as they are still running the discount. If you don't have the budget for those or are shopping for lower capacity drives then Crucial's T500 Gen4 drive discount is still live, and you can get them for just $125. And while the G50 4TB deal has expired, Team Group is now offering its 2TB model at its lowest ever price and you also get a free Micro SD card with it. The Team Group G50 is also a TLC (triple level cell) NAND flash SSD, and thus the endurance on the T-FORCE SSD is quite good, as it is rated for 1300 TBW (terabytes written) for the 2TB variant. Its MTBF, or Mean Time Between Failure, is claimed at 3,000,000 hours. The operating temperature is 0~70 C. The G50 does not have a dedicated DRAM cache (only the G50 Pro SKUs have it), but since it is based on NVMe version 1.4 which supports HMB (host memory buffer) technology; thus, the drive can use system memory for caching. In terms of performance, Team Group promises sequential read and write speeds of up to 5000 MB/s and 4500 MB/s, respectively. However, the firm does not disclose random throughput metrics. Get the Team Group G50 at the link below (deal is said to be ending in less than 10 hours): Team Group T-FORCE G50 SSD (TM8FFE002T0C129) + Team Group 64GB Elite microSDXC UHS-I U3, V30, A1, Micro SD with SD Adapter, to 100MB/s (TEAUSDX64GIV30A103): $105.99 + $12 off with promo code SSETA665 (Shipped and Sold by Newegg US) This Amazon deal is US-specific and not available in other regions unless specified. If you don't like it or want to look at more options, check out the Amazon US deals page here. Get Prime (SNAP), Prime Video, Audible Plus or Kindle / Music Unlimited. Free for 30 days. As an Amazon Associate, we earn from qualifying purchases.
    • I know what you're getting at, but Microsoft themselves have said that the Xbox Ally specifically disables a bunch of stuff from Windows to improve performance and save 2GB of memory. And that special game mode is coming to Windows 11 next year.
    • It could be good old fashion neglect, lower priority focus, less resources then it use to vs active sabotage.
  • Recent Achievements

    • First Post
      Ian_ earned a badge
      First Post
    • Explorer
      JaviAl went up a rank
      Explorer
    • Reacting Well
      Cole Multipass earned a badge
      Reacting Well
    • Reacting Well
      JLP earned a badge
      Reacting Well
    • Week One Done
      Rhydderch earned a badge
      Week One Done
  • Popular Contributors

    1. 1
      +primortal
      646
    2. 2
      ATLien_0
      268
    3. 3
      Michael Scrip
      219
    4. 4
      +FloatingFatMan
      184
    5. 5
      Steven P.
      145
  • Tell a friend

    Love Neowin? Tell a friend!