Create an Entity Data Model From a Database Entity Framework 4. In my previous article, Entity Framework 4. FAQ Getting Started Guide we looked at some of the most frequently asked questions on Entity Framework 4. Make sure you read it before you move ahead. In this article, we will quickly jump to create our first Entity Framework application using Visual Studio 2. Before that, I want to introduce you to a core component of the Entity Framework, the Entity Data Model EDM. The EDM describes the structure of your Business objects, which includes the data types, relationship types, schema mapping and so on. In simple words, EDM is a bridge between your application and data store and lets you work at a conceptual level with your data, rather than the actual schema. With Entity Framework 4. Generate a Model from the Database Database First approach Generate a Database from a Model Model First approach new to EF 4. Code Generation using T4 Templates and POCO Code First approach new to EF 4. Let us create an Entity Data Model EDM from an existing database, say Northwind. I assume you have either downloaded Visual Studio 2. Ultimate Trial Edition or the free Visual Studio 2. Express Edition. Lets get started Step 1 Open Visual Studio 2. File New Project. A while back I built a simple constant current electronic load using an aluminum HDD cooler case as the heatsink. While it was sufficient for a few amps load under. PDF files that contain the Visual Studio 2005 documentation. I was impressed by the versatility and depth of the effects that were possible with this single plugin. DAVE HUSS, Photoshop User Topaz Adjust allows you to. Go to your project properties, either by rightclicking on the project and picking Properties or by picking Properties from the Project menu. Click on Debug, then. New products and capabilities introduced across the entire DevExpress product line with v17. I agree that type safety would be nice, but its much less helpful since its confined to the garage class. Its encapsulated and easily controlled then, so my point. MZNji.jpg' alt='Program Controlled Gridview' title='Program Controlled Gridview' />In the templates, select C or VB, Windows Console Application. Make sure the target framework is. NET Framework 4. 0. I have called the application EFConsole. Click Ok. Step 2 Right click on the EFConsole project in Solution Explorer Add New Item. Select the Data Template ADO. NET Entity Data Model and click Add. Note If you plan to use the same Entity Model in different projects, then make sure that you create your Entity Model as a separate class project. This way, you will be able to add its reference in multiple projects. Step 3 The Entity Data Model Wizard appears. Choose Generate From Database and click Next You have to now choose your Data Connection. If you have created connections previously, then they will show up in the list. I assume you have not, so click on the New Connection button and set up the connection properties to the Northwind database, as shown below Click OK to return to the wizard and you will see that the new connection is visible in the data connection dropdown. Our Entity Connection Settings will be stored in the App. Monster Hunter 2 Ps2 English Patch. Config file as Northwind. Entities. You can change the name to anything else you want. Click Next Step 4 The next step is to choose the Database Objects you want to include in your Entity Data Model EDM. To keep it simple, I am choosing two tables Customers and Orders. Call the model namespace as Northwind. Model The checkbox Pluralize or singularize generated object names gives us the ability to pluralize or singularize object names. This is new to EF 4. EF 3. 5, not being able to renamepluralize objects in the model, caused a great deal of confusion. Click Finish to complete the wizard. Congratulations, our EDM is ready You have just generated a Model defined by EDM, from the Northwind database. The screenshot shown above is the representation of your Entity Data Model in the designer. Query against the Entity Data Model If you recall, I had mentioned in my previous article Entity Framework 4. Nintendo Ds Emulator Download For Pc Desmume Mac. FAQ Getting Started Guide that we will be programming against a logical model rather than a physical database. You can use LINQ to Entities or Entity SQL to write queries against your model defined by EDM. Entity Framework behind the scenes uses ADO. NET provider to translate these queries to what SQL Server understands and bring back the results. Note Since we are connecting to SQL Server, we will not need any additional providers to make a connection. If you plan to use Oracle, DB2, My. SQL etc, make sure you look at the additional 3rd party providers for these databases. In this step, I will show you how to query against the model you have just created. We will write code that displays the Customer. Id and Company. Name of customers who have placed orders after the 1st of January, 1. Open Program. cs and write the following query in your Main method staticvoid Mainstring args    usingvar context new. Northwind. Entities            var cust. With. Orders context. Orders           . Whereo o. Order. Date new. Date. Time1. 99. 8, 1, 1        foreach var cust in cust. With. Orders                    Console. Write. Line0 from 1 Ordered Item on 2,                cust. Customer. Customer. ID,                cust. Customer. Company. Name,                cust. Order. Date                                Console. Read. Line     The following output should be generated on your console window There you go You have written your first query against your model. I hope you now see how EF provides a shift from Database oriented Data. Reader, Data. Set to Model oriented development. So instead of focusing on a Database, a developer starts focusing on the Entities that represents the Business Model of the application. I know there are a lot of questions running in your mind about the query we just wrote. Just hold on to these queries for now. They will soon get cleared in the forthcoming articles. Update If you are curious to know how EDM generated the code and translated the queries to something that SQL Server understands, read my article Exploring how the Entity Data Model EDM Generates Code and Executes Queries Entity Framework 4. I hope you liked this article and I thank you for viewing it. The entire source code of this article can be download over here. What is cool about generics, why use them Not needing to typecast is one of the biggest advantages of Java generics, as it will perform type checking at compile time. This will reduce the possibility of Class. Cast. Exceptions which can be thrown at runtime, and can lead to more robust code. But I suspect that youre fully aware of that. Every time I look at Generics it gives. I find the best part of. Java to be its simplicity and minimal. At first, I didnt see the benefit of generics either. I started learning Java from the 1. Java 5 was out at the time and when I encountered generics, I felt that it was more code to write, and I really didnt understand the benefits. Modern IDEs make writing code with generics easier. Most modern, decent IDEs are smart enough to assist with writing code with generics, especially with code completion. Heres an example of making an Maplt String, Integer with a Hash. Map. The code I would have to type in is Maplt String, Integer m new Hash. Maplt String, Integer. And indeed, thats a lot to type just to make a new Hash. Map. However, in reality, I only had to type this much before Eclipse knew what I needed Maplt String, Integer m new Ha. CtrlSpace. True, I did need to select Hash. Map from a list of candidates, but basically the IDE knew what to add, including the generic types. With the right tools, using generics isnt too bad. In addition, since the types are known, when retrieving elements from the generic collection, the IDE will act as if that object is already an object of its declared type there is no need to casting for the IDE to know what the objects type is. A key advantage of generics comes from the way it plays well with new Java 5 features. Heres an example of tossing integers in to a Set and calculating its total Setlt Integer set new Hash. Setlt Integer. In that piece of code, there are three new Java 5 features present First, generics and autoboxing of primitives allow the following lines set. The integer 1. 0 is autoboxed into an Integer with the value of 1. And same for 4. 2. Download The Scar Solution Ebook Free. Then that Integer is tossed into the Set which is known to hold Integers. Trying to throw in a String would cause a compile error. Next, for for each loop takes all three of those for int i set. First, the Set containing Integers are used in a for each loop. Each element is declared to be an int and that is allowed as the Integer is unboxed back to the primitive int. And the fact that this unboxing occurs is known because generics was used to specify that there were Integers held in the Set. Generics can be the glue that brings together the new features introduced in Java 5, and it just makes coding simpler and safer. And most of the time IDEs are smart enough to help you with good suggestions, so generally, it wont a whole lot more typing. And frankly, as can be seen from the Set example, I feel that utilizing Java 5 features can make the code more concise and robust. Edit An example without generics. The following is an illustration of the above Set example without the use of generics. It is possible, but isnt exactly pleasant Set set new Hash. Set. for Object o set. Integero. Note The above code will generate unchecked conversion warning at compile time. When using non generics collections, the types that are entered into the collection is objects of type Object. Therefore, in this example, a Object is what is being added into the set. In the above lines, autoboxing is in play the primitive int value 1. Integer objects, which are being added to the Set. However, keep in mind, the Integer objects are being handled as Objects, as there are no type information to help the compiler know what type the Set should expect. Object o set. This is the part that is crucial. The reason the for each loop works is because the Set implements the Iterable interface, which returns an Iterator with type information, if present. Iteratorlt T, that is. However, since there is no type information, the Set will return an Iterator which will return the values in the Set as Objects, and that is why the element being retrieved in the for each loop must be of type Object. Now that the Object is retrieved from the Set, it needs to be cast to an Integer manually to perform the addition total Integero. Here, a typecast is performed from an Object to an Integer. In this case, we know this will always work, but manual typecasting always makes me feel it is fragile code that could be damaged if a minor change is made else where. I feel that every typecast is a Class. Cast. Exception waiting to happen, but I digress. The Integer is now unboxed into an int and allowed to perform the addition into the int variable total. I hope I could illustrate that the new features of Java 5 is possible to use with non generic code, but it just isnt as clean and straight forward as writing code with generics. And, in my opinion, to take full advantage of the new features in Java 5, one should be looking into generics, if at the very least, allows for compile time checks to prevent invalid typecasts to throw exceptions at runtime.