The steps for adding the Northwind database to the Server Explorer depend on whether you want to use the SQL Server 2005 Express Edition database in the App_Data folder or if you have a Microsoft SQL Server 2000 or 2005 database server setup that you want to use instead.
If you do not have a SQL Server 2000 or 2005 database server to connect to, or you simply want to avoid having to add the database to a database server, you can use the SQL Server 2005 Express Edition version of the Northwind database that is located in the downloaded website's App_Data folder (NORTHWND.MDF).
C DAL Generator for SQL Server and MS Access
Alternatively, you may connect to a Northwind database installed on a database server. If the database server does not already have the Northwind database installed, you first must add it to database server by running the installation script included in this tutorial's download or by downloading the SQL Server 2000 version of Northwind and installation script directly from Microsoft's web site.
Once you have the database installed, go to the Server Explorer in Visual Studio, right-click on the Data Connections node, and choose Add Connection. If you don't see the Server Explorer go to the View / Server Explorer, or hit Ctrl+Alt+S. This will bring up the Add Connection dialog box, where you can specify the server to connect to, the authentication information, and the database name. Once you have successfully configured the database connection information and clicked the OK button, the database will be added as a node underneath the Data Connections node. You can expand the database node to explore its tables, views, stored procedures, and so on.
When working with data one option is to embed the data-specific logic directly into the presentation layer (in a web application, the ASP.NET pages make up the presentation layer). This may take the form of writing ADO.NET code in the ASP.NET page's code portion or using the SqlDataSource control from the markup portion. In either case, this approach tightly couples the data access logic with the presentation layer. The recommended approach, however, is to separate the data access logic from the presentation layer. This separate layer is referred to as the Data Access Layer, DAL for short, and is typically implemented as a separate Class Library project. The benefits of this layered architecture are well documented (see the "Further Readings" section at the end of this tutorial for information on these advantages) and is the approach we will take in this series.
All code that is specific to the underlying data source such as creating a connection to the database, issuing SELECT, INSERT, UPDATE, and DELETE commands, and so on should be located in the DAL. The presentation layer should not contain any references to such data access code, but should instead make calls into the DAL for any and all data requests. Data Access Layers typically contain methods for accessing the underlying database data. The Northwind database, for example, has Products and Categories tables that record the products for sale and the categories to which they belong. In our DAL we will have methods like:
For example, the DataReader and the DataSet (by default) are loosely-typed objects since their schema is defined by the columns returned by the database query used to populate them. To access a particular column from a loosely-typed DataTable we need to use syntax like: DataTable.Rows[index]["columnName"]. The DataTable's loose typing in this example is exhibited by the fact that we need to access the column name using a string or ordinal index. A strongly-typed DataTable, on the other hand, will have each of its columns implemented as properties, resulting in code that looks like: DataTable.Rows[index].columnName.
Keep in mind that strongly-typed DataTables do not include any information on how to access data from their underlying database table. In order to retrieve the data to populate the DataTable, we use a TableAdapter class, which functions as our Data Access Layer. For our Products DataTable, the TableAdapter will contain the methods GetProducts(), GetProductByCategoryID(categoryID), and so on that we'll invoke from the presentation layer. The DataTable's role is to serve as the strongly-typed objects used to pass data between the layers.
At this point we have a Typed DataSet with a single DataTable (Northwind.Products) and a strongly-typed DataAdapter class (NorthwindTableAdapters.ProductsTableAdapter) with a GetProducts() method. These objects can be used to access a list of all products from code like:
This code did not require us to write one bit of data access-specific code. We did not have to instantiate any ADO.NET classes, we didn't have to refer to any connection strings, SQL queries, or stored procedures. Instead, the TableAdapter provides the low-level data access code for us.
We are first prompted about whether we want to access the database using an ad-hoc SQL statement or a new or existing stored procedure. Let's choose to use an ad-hoc SQL statement again. Next, we are asked what type of SQL query we'd like to use. Since we want to return all products that belong to a specified category, we want to write a SELECT statement which returns rows.
The next step is to define the SQL query used to access the data. Since we want to return only those products that belong to a particular category, I use the same SELECT statement from GetProducts(), but add the following WHERE clause: WHERE CategoryID = @CategoryID. The @CategoryID parameter indicates to the TableAdapter wizard that the method we're creating will require an input parameter of the corresponding type (namely, a nullable integer).
In the final step we can choose which data access patterns to use, as well as customize the names of the methods generated. For the Fill pattern, let's change the name to FillByCategoryID and for the return a DataTable return pattern (the GetX methods), let's use GetProductsByCategoryID.
You can use My Generations code generator to automatically generate your code, it have many templates on their site and you can also customize those templates as per your need. Just search out the appropriate template as per your requirements.
An added bonus is that connection management is now out of your hands, and you can extend the business entities as you wish, while knowing the the underlying DAL access code is mostly auto generated as well. It's a bit rudimentary, but if you're not looking for a lot of bells and whistles, this is a reasonable way to start.
DAL Method Generator is a simple utility to generate data access layer methods in C# for SQL Server stored procedures. Have you ever written too many data access layer methods in C# to connect to SQL server stored procedures? This utility could save your effort using few clicks.
The Data Access Layer, from here on out referred to as the DAL, is the layer of application functionality that encapsulates all interactions with the database. Typically this type of code is hand written and requires specialized knowledge, not only of .NET, but of the specific data access routines too. Writing the DAL code for an application is one of the most monotonous, time consuming, repetitive, and likely bug-ridden aspects of building software.
As mentioned in the introduction, CodeSmith is a template driven code generation tool. There is a window on the right of CodeSmith called the Template Explorer. The Template Explorer provides you with a quick and easy way of accessing the templates you've installed or written:
The Properties window allows you to set properties for the template. When using the Hashtable.cst template we need to set some common elements such as the generated ClassName, ItemType, and KeyType. For example, if you wanted to create a strongly typed collection of Person objects accessed by an integer with a class name of PersonCollection, you would set the ClassName to PersonCollection, the ItemType to Person, and the KeyType to int. You could generate the source for this strongly typed collection now by simply clicking the Run button in CodeSmith (found on the toolbar).
ASP.NET is a server-side web application framework created by Microsoft that runs on Windows and was started in the early 2000s. ASP.NET allows developers to make web applications, web services, and dynamic content-driven websites. The latest version of ASP.NET is 4.7.1 To learn how to set up projects in visual studio and how to create a database, refer to below-given links:
Where the need for a database is not very high, Microsoft Access offers numerous advantages over database solutions such as SQL Server and Oracle. With the help of Microsoft Access, many smaller teams can now avoid purchasing massive resources for their basic and simple needs. Furthermore, unlike traditional client-server databases, they do not require anyone to administer or monitor Access in MS Access.
Many applications that were previously relegated to a client-server database have been taken over by personal computer applications such as Microsoft Access. Access users do not need to undergo any special training to learn how to use the application. Using a readily available, well-organized set of templates, creating and administering a database is quite simple and easy.
Easy to integrate into your framework of choice, Prisma simplifies database access, saves repetitive CRUD boilerplate and increases type safety. Its the perfect companion for building production-grade, robust and scalable web applications. 2ff7e9595c
Comments