Text version of the video Slides All C Text Articles All C Slides Complete C tutorial All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic In this part of the c sharp tutorial we will learn about the differences between abstract classes and interfaces


cross apply sql server example sql server outer apply example sql server join table function with parameter sql server inner join table valued function In this video we will discuss cross apply and outer apply in sql server with examples. We want to retrieve all the matching rows between Department and Employee tables. This can be very easily achieved using an Inner Join as shown below. Select D.DepartmentName, E.Name, E.Gender, E.Salary from Department D Inner Join Employee E On D.Id = E.DepartmentId Now if we want to retrieve all the matching rows between Department and Employee tables + the non-matching rows from the LEFT table (Department) This can be very easily achieved using a Left Join as shown below. Select D.DepartmentName, E.Name, E.Gender, E.Salary from Department D Left Join Employee E On D.Id = E.DepartmentId Now let's assume we do not have access to the Employee table. Instead we have access to the following Table Valued function, that returns all employees belonging to a department by Department Id. Create function fn_GetEmployeesByDepartmentId(@DepartmentId int) Returns Table as Return ( Select Id, Name, Gender, Salary, DepartmentId from Employee where DepartmentId = @DepartmentId ) Go The following query returns the employees of the department with Id =1. Select * from fn_GetEmployeesByDepartmentId(1) Now if you try to perform an Inner or Left join between Department table and fn_GetEmployeesByDepartmentId() function you will get an error. Select D.DepartmentName, E.Name, E.Gender, E.Salary from Department D Inner Join fn_GetEmployeesByDepartmentId(D.Id) E On D.Id = E.DepartmentId If you execute the above query you will get the following error Msg 4104, Level 16, State 1, Line 3 The multi-part identifier D.Id could not be bound. This is where we use Cross Apply and Outer Apply operators. Cross Apply is semantically equivalent to Inner Join and Outer Apply is semantically equivalent to Left Outer Join. Just like Inner Join, Cross Apply retrieves only the matching rows from the Department table and fn_GetEmployeesByDepartmentId() table valued function. Select D.DepartmentName, E.Name, E.Gender, E.Salary from Department D Cross Apply fn_GetEmployeesByDepartmentId(D.Id) E Just like Left Outer Join, Outer Apply retrieves all matching rows from the Department table and fn_GetEmployeesByDepartmentId() table valued function + non-matching rows from the left table (Department) Select D.DepartmentName, E.Name, E.Gender, E.Salary from Department D Outer Apply fn_GetEmployeesByDepartmentId(D.Id) E How does Cross Apply and Outer Apply work The APPLY operator introduced in SQL Server 2005, is used to join a table to a table-valued function. The Table Valued Function on the right hand side of the APPLY operator gets called for each row from the left (also called outer table) table. Cross Apply returns only matching rows (semantically equivalent to Inner Join) Outer Apply returns matching + non-matching rows (semantically equivalent to Left Outer Join). The unmatched columns of the table valued function will be set to NULL. Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Link for all dot net and sql server video tutorial playlists Link for slides, code samples and text version of the video In this video we will understand closures in JavaScript with an example. What is a closure A closure is an inner function that has access to the outer function’s variables in addition to it's own variables and global variables. The inner function has access not only to the outer function’s variables, but also to the outer function’s parameters. You create a closure by adding a function inside another function. JavaScript Closure Example function addNumbers(firstNumber, secondNumber) var returnValue = Result is : ; // This inner function has access to the outer function's variables & parameters function add() return returnValue + (firstNumber + secondNumber); return add(); var result = addNumbers(10, 20); document.write(result); Output : Result is : 30 The following code Returns the inner function expression function addNumbers(firstNumber, secondNumber) var returnValue = Result is : ; function add() return returnValue + (firstNumber + secondNumber); // We removed the parentheses. This will return the inner function expression without executing it. return add; // addFunc will contain add() function (inner function) expression. var addFunc = addNumbers(10, 20); // call the addFunc() function and store the return value in result variable var result = addFunc(); document.write(result); Returning and executing the inner function function addNumbers(firstNumber, secondNumber) var returnValue = Result is : ; function add() return returnValue + (firstNumber + secondNumber); // We removed the parentheses. This will return the inner function add() expression without executing it. return add; // This returns add() function (inner function) definition and executes it. Notice the additonal parentheses. var result = addNumbers(10, 20)(); document.write(result);


Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic When can a deadlock occur In a database, a deadlock occurs when two or more processes have a resource locked, and each process requests a lock on the resource that another process has already locked. Neither of the transactions here can move forward, as each one is waiting for the other to release the lock. When deadlocks occur, SQL Server will choose one of processes as the deadlock victim and rollback that process, so the other process can move forward. The transaction that is chosen as the deadlock victim will produce the following error. Msg 1205, Level 13, State 51, Line 1 Transaction (Process ID 57) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction. SQL script to create the tables and populate them with test data Create table TableA ( Id int identity primary key, Name nvarchar(50) ) Go Insert into TableA values ('Mark') Go Create table TableB ( Id int identity primary key, Name nvarchar(50) ) Go Insert into TableB values ('Mary') Go The following 2 transactions will result in a dead lock. Open 2 instances of SQL Server Management studio. From the first window execute Transaction 1 code and from the second window execute Transaction 2 code. -- Transaction 1 Begin Tran Update TableA Set Name = 'Mark Transaction 1' where Id = 1 -- From Transaction 2 window execute the first update statement Update TableB Set Name = 'Mary Transaction 1' where Id = 1 -- From Transaction 2 window execute the second update statement Commit Transaction -- Transaction 2 Begin Tran Update TableB Set Name = 'Mark Transaction 2' where Id = 1 -- From Transaction 1 window execute the second update statement Update TableA Set Name = 'Mary Transaction 2' where Id = 1 -- After a few seconds notice that one of the transactions complete -- successfully while the other transaction is made the deadlock victim Commit Transaction Next Video : We will discuss the criteria SQL Server uses to choose a deadlock victim


Text version of the video Slides All C Text Articles All C Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic In this part of the c sharp tutorial we will learn the difference between method overriding and method hiding


Link for code samples used in the demo Link for all dot net and sql server video tutorial playlists In this video we will discuss What is WCF Why should we use WCF What is WCF? WCF stands for Windows Communication Foundation and is part of.NET 3.0. WCF is Microsoft platform for building distributed and interoperable applications. What is a distributed application? In simple terms a distributed application, is an application where parts of it run on 2 or more computers. Distributed applications are also called as connected systems or applications. Examples: A web application running on one machine and a web service that this application is consuming is running on another machine. An enterprise web application may have the following tiers, and each tier may be running on a different machine 1. Presentation tier 2. Business tier 3. Data Access tier Why build distributed applications? There are several reasons for this 1. An enterprise application may need to use the services provided by other enterprises. For example an ecommerce application may be using paypal service for payments. 2. For better scalability. An enterprise web application may have Presentation tier, Business tier, and Data Access tiert, and each tier may be running on a different machine. What is an interoperable application? An application that can communicate with any other application that is built on any platform and using any programming language is called as an interoperable application. Web services are interoperable, where as.NET remoting services are not. Web services can communicate with any application built on any platform, where as a.NET remoting service can be consumed only by a.net application. What technology choices did we have before WCF to build distributed applications? Enterprise Services Dot Net Remoting Web Services Why should we use WCF? Let's take this scenario We have 2 clients and we need to implement a service a for them. 1. The first client is using a Java application to interact with our service, so for interoperability this client wants messages to be in XML format and the protocol to be HTTP. 2. The second client uses.NET, so for better performance this client wants messages formmated in binary over TCP protocol. Without WCF 1. To satisfy the first client requirement we end up implementing an ASMX web service, and 2. To satisfy the second client requirement we end up implementing a remoting service These are 2 different technologies, and have complete different programming models. So the developers have to learn different technologies. So to unify and bring all these technologies under one roof Microsoft has come up with a single programming model that is called as WCF - Windows Communication Foundation. With WCF, You implement one service and we can configure as many end points as want to support all the client needs. To support the above 2 client requirements, we would configure 2 end points. In the endpoint configuration we can specify the protocols and message formats that we want to use. In Part 2, we will discuss implementing 1. A web service to exchange messages in XML format using HTTP protocol for interoperability. 2. A remoting service to exchange messages in binary format using TCP protocol for performance. Along the way, we will get a feel of how different these technologies are. In Part 3, we will dicuss implementing a single WCF Service and configuring different end points to support different transport protocols and message formats.


sql server where vs having sql server group by where having group by having sql server In this vide we will discuss the difference between where and having caluses in sql server. Let us understand the difference with an example. To calculate total sales by product, we would write a GROUP BY query as shown below SELECT Product, SUM(SaleAmount) AS TotalSales FROM Sales GROUP BY Product Now if we want to find only those products where the total sales amount is greater than $1000, we will use HAVING clause to filter products SELECT Product, SUM(SaleAmount) AS TotalSales FROM Sales GROUP BY Product HAVING SUM(SaleAmount) ] 1000 If we use WHERE clause instead of HAVING clause, we will get a syntax error. This is because the WHERE clause doesn’t work with aggregate functions like sum, min, max, avg, etc. SELECT Product, SUM(SaleAmount) AS TotalSales FROM Sales GROUP BY Product WHERE SUM(SaleAmount) ] 1000 So in short, the difference is WHERE clause cannot be used with aggregates where as HAVING can. However, there are other differences as well that we need to keep in mind when using WHERE and HAVING clauses. WHERE clause filters rows before aggregate calculations are performed where as HAVING clause filters rows after aggregate calculations are performed. Let us understand this with an example. Total sales of iPhone and Speakers can be calculated by using either WHERE or HAVING clause Calculate Total sales of iPhone and Speakers using WHERE clause : In this example the WHERE clause retrieves only iPhone and Speaker products and then performs the sum. SELECT Product, SUM(SaleAmount) AS TotalSales FROM Sales WHERE Product in ('iPhone', 'Speakers') GROUP BY Product Calculate Total sales of iPhone and Speakers using HAVING clause : This example retrieves all rows from Sales table, performs the sum and then removes all products except iPhone and Speakers. SELECT Product, SUM(SaleAmount) AS TotalSales FROM Sales GROUP BY Product HAVING Product in ('iPhone', 'Speakers') So from a performance standpoint, HAVING is slower than WHERE and should be avoided when possible. Another difference is WHERE comes before GROUP BY and HAVING comes after GROUP BY. Difference between WHERE and Having 1. WHERE clause cannot be used with aggregates where as HAVING can. This means WHERE clause is used for filtering individual rows where as HAVING clause is used to filter groups. 2. WHERE comes before GROUP BY. This means WHERE clause filters rows before aggregate calculations are performed. HAVING comes after GROUP BY. This means HAVING clause filters rows after aggregate calculations are performed. So from a performance standpoint, HAVING is slower than WHERE and should be avoided when possible. 3. WHERE and HAVING can be used together in a SELECT query. In this case WHERE clause is applied first to filter individual rows. The rows are then grouped and aggregate calculations are performed, and then the HAVING clause filters the groups. Text version of the video Slides All SQL Server Text Articles All SQL Server Slides Full SQL Server Course All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn about, database normalization, different normal forms, problems of data redundancy, first normal form, that is how to put a table in 1 NF. Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn about 1. Different types of indexes in sql server 2. What are clustered indexes 3. What are NonClustered indexes 4. Difference between clustered and non clustered indexes Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will discuss all that you need to know to become a successful asp.net web application developer Essential skills : The following are the essential skills that you need to learn in the order specified to become a web developer 1. Dot Net Basics : Learn what is Dot Net all about and how it works. All dot net developers, irrespective of whether you are a web or windows developer, need to know about these concepts. 2. One Programming language (C or VB.NET) : You must learn at least on of the programming language (C or VB.NET) to build dynamic data driven web applications. These videos start from the basics and covers all the advanced aspects of c programming language that an asp.net web developer needs to know. 3. SQL Server : SQL Server is a database that stores the web application data. You need to learn the SQL programming language to store and retrieve data from the database server, which helps us build data driven web application. 4. ASP.NET : This is the framework that.NET provides to build web applications. 5. ADO.NET : Enables an asp.net web application to communicate with the database to store and retrieve data. 6. ASP.NET GridView - This is one of the widely used data control in an asp.net web application that enables to display, insert, update and delete data. 7. Visual Studio - This is the development tool/software that we use to build Dot Net applications. In addition to the above 7 essential skills, you also need to know the basics of HTML. HTML is very easy to self learn and there are many free resources on the web already. Nice to have skills : These days a lot of organisations are also looking for the following skills in addtion to the above essential skills. If you want to increase the chances of getting your resume shortlisted for an interview call, then you also need to be familiar (if not proficient) with the following technologies. 1. ASP.NET Web Services : ASP.NET Web Services became a legacy technology with the introduction of WCF. However, there are many organisations that are still using ASP.NET web services, so if you want to increase your chances of an interview call you may want to learn this technology as well. Also, learning asp.net web services, makes it easy to learn WCF. 2. WCF : Helps buils service oriented applications. If you are familiar with this and if you can answer the interview questions you almost have the job. 3. ASP.NET MVC - Gives you a powerful, patterns-based way to build dynamic websites that enables a clean separation of concerns and that gives you full control. 3. Entity Framework : This is an ORM framework that enables.NET developers to work with relational data using domain-specific objects. Another nice to have skill. 4. LINQ - Language-Integrated Query (LINQ) is a set of features introduced in Visual Studio 2008 that extends powerful query capabilities to the language syntax of C and Visual Basic. The different aspects of LINQ are covered in the following tutorials. LINQ LINQ to XML LINQ to SQL In addition to the above 4 nice to have skills, you also need to know jQuery. I don't have a video series on this yet, but there are several resources on the web already. To help you with your interview preparation, I have also started several video series as listed below. C Interview Questions & Answers Dot Net Written Test Questions & Answers SQL Server Interview Questions & Answers Slides, code samples and text version of the videos are available on my blog. All these resources are available at no cost. In total there are over 700 videos (150 Hours). This means if you spend 5 hours a day watching these videos in 30 days you have most of the skills required to become a successful asp.net web developer. If you need a video on a concept that you are struggling with or if you have attended an interview and if you need a question to be answered, please leave it as a comment and I shall record and upload video answering it as soon as I can. If you need a DVD with all the videos and slides or if you need to download the videos for offline viewing, please visit the following link. Finally if you feel these videos could help others like you please share on Facebook, Google+ and any other social media you use. Enjoy Coding Venkat


Link for code samples used in the demo Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists What are action filters in asp.net mvc? Action filters are attributes that can be applied either on a controller action method or on a controller. When applied at the controller level, they are applicable for all actions within that controller. Action filters allow us to add, pre and post processing logic to an action method. This means, they allow us to modify the way in which an action is executed. Name a few action filters in mvc? Authorize ChildActionOnly HandleError OutputCache RequireHttps ValidateInput ValidateAntiForgeryToken We will discuss each of these action filters in detail in our upcoming videos. Can you create a custom action filter in mvc? Yes, we will discuss this in a later video session.


In this video we will discuss FIRST_VALUE function in SQL Server FIRST_VALUE function Introduced in SQL Server 2012 Retrieves the first value from the specified column ORDER BY clause is required PARTITION BY clause is optional Syntax : FIRST_VALUE(Column_Name) OVER (ORDER BY Col1, Col2.) FIRST_VALUE function example WITHOUT partitions : In the following example, FIRST_VALUE function returns the name of the lowest paid employee from the entire table. SELECT Name, Gender, Salary, FIRST_VALUE(Name) OVER (ORDER BY Salary) AS FirstValue FROM Employees FIRST_VALUE function example WITH partitions : In the following example, FIRST_VALUE function returns the name of the lowest paid employee from the respective partition. SELECT Name, Gender, Salary, FIRST_VALUE(Name) OVER (PARTITION BY Gender ORDER BY Salary) AS FirstValue FROM Employees Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Text version of the video Slides All C Text Articles All C Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic In this part of the c sharp tutorial we will learn 1. Method hiding 2. Invoke hidden base class members


Text version of the video Slides All C Interview Questions Text Articles & Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Benefits of using stored procedures over inline sql or adhoc sql Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Link for code samples used in the demo Link for all dot net and sql server video tutorial playlists This question can also be asked in a slightly different way How to handle exceptions that occur in finally block The exception propagates up, and should be handled at a higher level. If the exception is not handled at the higher level, the application crashes. The finally block execution stops at the point where the exception is thrown. In the example below, notice that the finally block in Hello() method throws an exception. Hello() method is being called in the Main() method and we don't have any exception handling mechanism in place in the Main() method. So, the application crashes with the exception. public class Program public static void Main() Hello(); public static void Hello() try // Some code catch // Some code finally Console.WriteLine( This line will be executed ); int result = Convert.ToInt32( TEN ); Console.WriteLine( This line will NOT be executed ); On the other hand, if you include exception handling mechanism(try/catch) in the Main() method, then you will have the opportunity to handle the exception. public static void Main() try Hello(); catch (Exception ex) // Process and log the exception Console.WriteLine(ex.Message); Irrespective of whether there is an exception or not finally block is guaranteed to execute. 1. If the finally block is being executed after an exception has occurred in the try block, 2. and if that exception is not handled 3. and if the finally block throws an exception Then the original exception that occurred in the try block is lost. Here is an example: public class Program public static void Main() try Hello(); catch (Exception ex) Console.WriteLine(ex.Message); public static void Hello() try // This exception will be lost throw new Exception( Exception in TRY block ); finally throw new Exception( Exception in FINALLY block );


Link for all dot net and sql server video tutorial playlists Link for slides, code samples and text version of the video In this video we will discuss 1. What are Extension Methods 2. How to implement extension methods What are Extension Methods According to MSDN, Extension methods enable you to add methods to existing types without creating a new derived type, recompiling, or otherwise modifying the original type. Extension methods are a special kind of static method, but they are called as if they were instance methods on the extended type. For client code written in C and Visual Basic, there is no apparent difference between calling an extension method and the methods that are actually defined in a type. Let us understand what this definition actually means. LINQ's standard query operators (select, where etc ) are implemented in Enumerable class as extension methods on the IEnumerable[T] interface. Now look at the following query List[int] Numbers = new List[int] 1, 2, 3 ,4, 5, 6, 7, 8, 9, 10 ; IEnumerable[int] EvenNumbers = Numbers.Where(n =] n % 2 == 0); Inspite of Where() method not belonging to List[T] class, we are still able to use it as though it belong to List[T] class. This is possible because Where() method is implemented as extension method in IEnumerable[T] interface and List[T] implements IEnumerable[T] interface. How to implement extension methods We want to define a method in the string class (let's call it ChangeFirstLetterCase), which will change the case of the first letter of the string. For example, if the first letter of the string is lowercase the function should change it to uppercase and viceversa. We want to be able to call this function on the string object as shown below. string result = strName.ChangeFirstLetterCase(); Defining ChangeFirstLetterCase() method directly in the string class is not possible as we don't own the string class. It belongs to.NET framework. Another alternative is to write a wrapper class as shown below. public class StringHelper public static string ChangeFirstLetterCase(string inputString) if (inputString.Length ] 0) char[] charArray = inputString.ToCharArray(); charArray[0] = char.IsUpper(charArray[0]) ? char.ToLower(charArray[0]) : char.ToUpper(charArray[0]); return new string(charArray); return inputString; Wrapper class works, but the problem is, we cannot call ChangeFirstLetterCase() method using the following syntax. string result = strName.ChangeFirstLetterCase(); Instead we have to call it as shown below. string result = StringHelper.ChangeFirstLetterCase(strName); Convert ChangeFirstLetterCase() method to an extension method to be able to call it using the following syntax, as though it belongs to string class. string result = strName.ChangeFirstLetterCase(); To convert ChangeFirstLetterCase() method to an extension method, make the following 2 changes 1. Make StringHelper static class 2. The type the method extends should be passed as a first parameter with this keyword preceeding it. With these 2 changes, we should be able to call this extension method in the same way we call an instance method. Notice that the extension method shows up in the intellisense as well, but with a different visual clue. string result = strName.ChangeFirstLetterCase(); Please note that, we should still be able to call this extension method using wrapper class style syntax. In fact, behind the scene this is how the method actually gets called. Extension methods are just a syntactic sugar. string result = StringHelper.ChangeFirstLetterCase(strName); So, this means we should also be able to call LINQ extension methods (select, where etc), using wrapper class style syntax. Since all LINQ extension methods are defined in Enumerable class, the syntax will be as shown below. List[int] Numbers = new List[int] 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ; IEnumerable[int] EvenNumbers = Enumerable.Where(Numbers, n =] n % 2 == 0);


Link for all dot net and sql server video tutorial playlists Link for slides, code samples and text version of the video In this video we will discuss Prototype object in JavaScript. Let us understand it's use with an example. The following Employee constructor function constructs Employee object. function Employee(name) this.name = name; There are several ways to add a function to the Employee object. One way is as shown below. This works but the problem with this approach is that, if you create 100 employee objects there will be 100 copies of getName() function. We don't want to be creating copies of functions, instead we want all the objects to share the same function code. This can be achieved using JavaScript prototype object. function Employee(name) this.name = name; this.getName = function () return this.name; var e1 = new Employee( Mark ); var e2 = new Employee( Sara ); document.write( e1.name = + e1.getName() + [br/] ); document.write( e2.name = + e2.getName() + [br/] ); Output : e1.name = Mark e2.name = Sara In this example, getName() function is added just to e1 object, and not to e2 object. So e2.getName() would throw an undefined error. function Employee(name) this.name = name; var e1 = new Employee( Mark ); e1.getName = function () return this.name; var e2 = new Employee( Sara ); document.write( e1.name = + e1.getName() + [br/] ); document.write( e2.name = + e2.getName() + [br/] ); In the following example getName() function is added to the Employee object using the name of the constructor function. This would also result in undefined error. function Employee(name) this.name = name; Employee.getName = function () return this.name; var e1 = new Employee( Mark ); var e2 = new Employee( Sara ); document.write( e1.name = + e1.getName() + [br/] ); document.write( e2.name = + e2.getName() + [br/] ); Using the prototype object to add functions : The following are the advantages of using the prototype object to add functions. 1. No matter how many objects you create, functions are loaded only once into memory 2. Allows you to override functions if required. function Employee(name) this.name = name; Employee.prototype.getName = function () return this.name; var e1 = new Employee( Mark ); var e2 = new Employee( Sara ); document.write( e1.name = + e1.getName() + [br/] ); document.write( e2.name = + e2.getName() + [br/] ); Output : e1.name = Mark e2.name = Sara


Text version of the video Slides Angular 2 Tutorial playlist Angular 2 Text articles and slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic So far Google has released 3 versions of Angular Version Year ------------ ------ AngularJS 2010 Angular 2 2016 Angular 4 2017 What is the difference between AngularJS and Angular 2 The first version of Angular is called AngularJS and was released in the year 2010. Some people call it Angular 1, but it is officially called AngularJS. Angular 2 is released in the year 2016. The most important thing to keep in mind is that, Angular 2 is not a simple upgrade from angular 1. Angular 2 is completely rewritten from the ground up and as a result the way we write applications with AngularJS and Angular 2 is very different. From a performance standpoint, Angular 2 is 5 times faster compared to AngularJS. AngularJS was not built for mobile devices, where as Angular 2 on the other hand is designed from the ground up with mobile support in mind. With Angular 2 we have more language choices. In additon to nativa JavaScript we can use TypeScript, Dart, PureScript, Elm, etc. Angular 4 is released in 2017. So, What is the difference between Angular 2 and Angular 4 If you have worked with both Angular 1 and Angular 2, then you already know that the API's and patterns that we use to build applications are very different between these 2 versions. From a developer stand point, it is like learning 2 different frameworks. Since Angular 2 is a complete rewrite from Angular 1, moving from Angular 1 to Angular 2 is a total breaking change. However, changing from Angular 2 to Angular 4 and even future versions of Angular, won’t be like changing from Angular 1. It won’t be a complete rewrite, it will simply be a change in some core libraries. From a developer standpoint, building an application using Angular 2 and Angular 4 is not very different. We still use the same concepts and patterns. Angular 4 is simply, the next version of Angular 2. The underlying concepts are still the same and if you have already learnt Angular 2 then you’re well prepared to switch to Angular 4. The most important point to keep in mind is, Angular 4 is backwards compatible with Angular 2 for most applications. What has changed and what is new in Angular 4 Some under the hood changes to reduce the size of the AOT (Ahead-of-Time) compiler generated code. Migrating to Angular 4 may reduce the production bundles by hundreds of kilobytes. As a developer this change will not affect the way we write angular applications in any way. TypeScript 2.1 and 2.2 compatibility. Angular is updated with a more recent version of TypeScript, for better type checking throughout our application. Up until Angular 4, only TypeScript 1.8 was supported. With Angular 4, we can use typescript 2.1 or 2.2 which means we can use all the new features of TypeScript with Angular 4. Animation features are pulled out of @angular/core and are moved into their own package. This means that if you don’t use animations, this extra code will not end up in your production bundles. On the other hand, if you do have animations in your application, you may have to change your existing code to pull the animation features from the animations package. We can now use an if/else style syntax with *ngIf structural directive. In Angular 2, to implement if/else logic, we use 2 *ngIf structural directives. With Angular 4, we can use it's new if/else style syntax with *ngIf structural directive. We will discuss an example of this in our upcoming videos. What happened to Angular 3. Why did we move straight from Angular 2 to Angular 4. What is the reason for skipping Angular 3. Except the Router library, all the other Angular core libraries are versioned the same way and are shipped as NPM packages as you can see below. While all the other core angular packages are at Version 2, the router library is already at Version 3. Due to this misalignment of the router package’s version, the angular team decided to go straight for Angular v4. This way, all the core packages are aligned which will be easier to maintain and help avoid confusion in the future. Common Questions Do I have to learn AngularJS 1 before learning Angular 2 Do I have to learn Angular 2 before learning Angular 4


Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic In this video we will discuss 1. What a transaction is 2. The problems that might arise when tarnsactions are run concurrently 3. The different transaction isolation levels provided by SQL Server to address concurrency side effects First let us understand what is a transaction A transaction is a group of commands that change the data stored in a database. A transaction, is treated as a single unit of work. A transaction ensures that, either all of the commands succeed, or none of them. If one of the commands in the transaction fails, all of the commands fail, and any data that was modified in the database is rolled back. In this way, transactions maintain the integrity of data in a database. Example : The following transaction ensures that both the UPDATE statements succeed or both of them fail if there is a problem with one UPDATE statement. -- Transfer $100 from Mark to Mary Account BEGIN TRY BEGIN TRANSACTION UPDATE Accounts SET Balance = Balance - 100 WHERE Id = 1 UPDATE Accounts SET Balance = Balance + 100 WHERE Id = 2 COMMIT TRANSACTION PRINT 'Transaction Committed' END TRY BEGIN CATCH ROLLBACK TRANSACTION PRINT 'Transaction Rolled back' END CATCH Databases are powerful systems and are potentially used by many users or applications at the same time. Allowing concurrent transactions is essential for performance but may introduce concurrency issues when two or more transactions are working with the same data at the same time. Some of the common concurrency problems Dirty Reads Lost Updates Nonrepeatable Reads Phantom Reads We will discuss what these problems are in detail with examples in our upcomning videos One way to solve all these concurrency problems is by allowing only one user to execute, only one transaction at any point in time. Imagine what could happen if you have a large database with several users who want to execute several transactions. All the transactions get queued and they may have to wait a long time before they could get a chance to execute their transactions. So you are getting poor performance and the whole purpose of having a powerful database system is defeated if you serialize access this way. At this point you might be thinking, for best performance let us allow all transactions to execute concurrently. The problem with this approach is that it may cause all sorts of concurrency problems (i.e Dirty Reads, Lost Updates, Nonrepeatable Reads, Phantom Reads) if two or more transactions work with the same data at the same time. SQL Server provides different transaction isolation levels, to balance concurrency problems and performance depending on our application needs. Read Uncommitted Read Committed Repeatable Read Snapshot Serializable The isolation level that you choose for your transaction, defines the degree to which one transaction must be isolated from resource or data modifications made by other transactions. Depending on the isolation level you have chosen you get varying degrees of performance and concurrency problems. The table here has the list of isoltaion levels along with concurrency side effects. Isolation Level Dirty Reads Lost Update Nonrepeatable Reads Phantom Reads Read Uncommitted Yes Yes Yes Yes Read Committed No Yes Yes Yes Repeatable Read No No No Yes Snapshot No No No No Serializable No No No No If you choose the lowest isolation level (i.e Read Uncommitted), it increases the number of concurrent transactions that can be executed at the same time, but the down side is you have all sorts of concurrency issues. On the other hand if you choose the highest isolation level (i.e Serializable), you will have no concurrency side effects, but the downside is that, this will reduce the number of concurrent transactions that can be executed at the same time if those transactions work with same data. In our upcoming videos we will discuss the concurrency problems in detail with examples


In this video we will discuss about Lead and Lag functions. Lead and Lag functions Introduced in SQL Server 2012 Lead function is used to access subsequent row data along with current row data Lag function is used to access previous row data along with current row data ORDER BY clause is required PARTITION BY clause is optional Syntax LEAD(Column_Name, Offset, Default_Value) OVER (ORDER BY Col1, Col2.) LAG(Column_Name, Offset, Default_Value) OVER (ORDER BY Col1, Col2.) Offset - Number of rows to lead or lag. Default_Value - The default value to return if the number of rows to lead or lag goes beyond first row or last row in a table or partition. If default value is not specified NULL is returned. We will use the following Employees table for the examples in this video SQL Script to create the Employees table Create Table Employees ( Id int primary key, Name nvarchar(50), Gender nvarchar(10), Salary int ) Go Insert Into Employees Values (1, 'Mark', 'Male', 1000) Insert Into Employees Values (2, 'John', 'Male', 2000) Insert Into Employees Values (3, 'Pam', 'Female', 3000) Insert Into Employees Values (4, 'Sara', 'Female', 4000) Insert Into Employees Values (5, 'Todd', 'Male', 5000) Insert Into Employees Values (6, 'Mary', 'Female', 6000) Insert Into Employees Values (7, 'Ben', 'Male', 7000) Insert Into Employees Values (8, 'Jodi', 'Female', 8000) Insert Into Employees Values (9, 'Tom', 'Male', 9000) Insert Into Employees Values (10, 'Ron', 'Male', 9500) Go Lead and Lag functions example WITHOUT partitions : This example Leads 2 rows and Lags 1 row from the current row. When you are on the first row, LEAD(Salary, 2, -1) allows you to move forward 2 rows and retrieve the salary from the 3rd row. When you are on the first row, LAG(Salary, 1, -1) allows us to move backward 1 row. Since there no rows beyond row 1, Lag function in this case returns the default value -1. When you are on the last row, LEAD(Salary, 2, -1) allows you to move forward 2 rows. Since there no rows beyond the last row 1, Lead function in this case returns the default value -1. When you are on the last row, LAG(Salary, 1, -1) allows us to move backward 1 row and retrieve the salary from the previous row. SELECT Name, Gender, Salary, LEAD(Salary, 2, -1) OVER (ORDER BY Salary) AS Lead_2, LAG(Salary, 1, -1) OVER (ORDER BY Salary) AS Lag_1 FROM Employees Lead and Lag functions example WITH partitions : Notice that in this example, Lead and Lag functions return default value if the number of rows to lead or lag goes beyond first row or last row in the partition. SELECT Name, Gender, Salary, LEAD(Salary, 2, -1) OVER (PARTITION By Gender ORDER BY Salary) AS Lead_2, LAG(Salary, 1, -1) OVER (PARTITION By Gender ORDER BY Salary) AS Lag_1 FROM Employees Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will discuss about Corelated Subqueries In Part 59, we discussed about 2 examples that uses subqueries. Please watch Part 59, before proceeding with this video. We will be using the same tables and queries from Part 59. In the example below, sub query is executed first and only once. The sub query resutls are then used by the outer query. In a non-corelated subquery, the subquery can be executed independently of the outer query. Select [Id], [Name], [Description] from tblProducts where Id not in (Select Distinct ProductId from tblProductSales) If the subquery depends on the outer query for its values, then that sub query is called as a correlated subquery. In the where clause of the subquery below, ProductId column get it's value from tblProducts table that is present in the outer query. So, here the subquery is dependent on the outer query for it's value, hence this subquery is a correlated subquery. Correlated subqueries get executed, once for every row that is selected by the outer query. corelated subquery, cannot be executed independently of the outer query. Select [Name], (Select SUM(QuantitySold) from tblProductSales where ProductId = tblProducts.Id) as TotalQuantity from tblProducts order by Name Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn 1. Grouping rows using GROUP BY 2. Filtering Groups 3. Difference between WHERE and HAVING clause in sql server Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


AngularJS tutorial - What is AngularJS In this video we will discuss What is AngularJS Benefits of AngularJS A simple AngularJS example What is AngularJS AngularJS is a JavaScript framework that helps build applications that run in a web browser. Who developed AngularJS Google is the company that developed AngularJS. AngularJS is an open source project, which means it can be be freely used, changed, and shared by anyone. AngularJS is an excellent framework for building both Single Page Applications (SPA) and Line of Business Applications. Many companies are using Angular today, and there are many public facing web sites that are built with angular. There is a website, , that has the list of web sites that are built using AngularJS. Within this list you can find many popular websites. What are the benefits of using AngularJS 1. Dependency Injection : Dependency Injection is something AngularJS does quite well. If you are new to Dependency Injection, don't worry, we will discuss it in detail with examples in a later video. 2. Two Way Data-Binding : One of the most useful feature in AngularJS is the Two Way Data-Binding. The Two Way Data-Binding, keeps the model and the view in sync at all times, that is a change in the model updates the view and a change in the view updates the model. 3. Testing : Testing is an area where Angular really shines. Angular is designed with testing in mind right from the start. Angular makes it very easy to test any of it's components through both unit testing and end to end testing. So there's really no excuse for not testing any of your angular application code. 4. Model View Controller : With angular it is very easy to develop applications in a clean MVC way. All you have to do is split your application code into MVC components. The rest, that is managing those components and connecting them together is done by angular. 5. Many more benefits like controlling the behaviour of DOM elements using directives and the flexibility that angular filters provide. We will discuss directives, filters, Modules, Routes etc with examples in our upcoming videos in this series. To build angular applications you only need one script file and that is angular.js. To get the script file visit . From here 1. You can download the angular script file 2. CDN link - We discussed the benefits of using CDN in Part 3 of jQuery tutorial. 3. Various resources to learn angular - Here you will find videos, Free courses, Tutorials and Case Studies. You will also find API reference which is extremeley useful. To get started with angular 1. Add a reference to the angular script 2. Include ng-app attribute What is ng-app In angular, ng-app is called a directive. There are many directives in angular. You can find the complete list of directives on . The ng prefix in the directive stands for angular. The ng-app directive is a starting point of AngularJS Application. Angular framework will first check for ng-app directive in an HTML page after the entire page is loaded. If ng-app directive is found, angular bootstraps itself and starts to manage the section of the page that has the ng-app directive. So the obvious next question is, where to place the ng-app directive on the page It should be placed at the root of the HTML document, that is at the [html] tag level or at the [body] tag level, so that angular can control the entire page. However, there is nothing stopping you from placing it on any other HTML element with in the page. When you do this only that element and it's children are managed by angular. Double curly braces are called binding expressions in angular. These All the following are valid expressions in angular 1 == 1 - Evaluates to true name: 'David', age : '30' .name - Returns the name property value ['Mark', 'David', 'Sara'][2] - Returns the 2nd element from the array Link for all dot net and sql server video tutorial playlists Link for slides, code samples and text version of the video


In this video we will learn about derived tables and common table expressions. CTE stands for common table expressions. We will also find the differences between, views, temporary tables, table variable, derived tables and cte's Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


twitter bootstrap tutorial for beginners twitter bootstrap for beginners benefits of bootstrap framework advantages of bootstrap framework twitter bootstrap benefits what is responsive web design what is responsive website what is responsive design use of bootstrap responsive web development responsive web app In this video we will discuss 1. What is bootstrap 2. Advantages of using bootstrap Bootstrap is a free, open-source and is the most popular HTML, CSS, and JavaScript framework developed by twitter for creating responsive web applications. It includes HTML and CSS based design templates for common user interface components like Buttons, Dropdowns, Typography, Tabs, Forms, Tables, Navigations, Alerts, Modals, Accordion, Carousel etc. along with optional JavaScript extensions. Bootstrap framework is based on open standards - HTML, CSS and JavaScript. This means bootstrap can be used with any server side technology and any platform. You can use it with any web application built with any server side technology like ASP.NET, JAVA, PHP etc. What are the advantages of using bootstrap Supports responsive design : One of the greatest advantages of using bootstrap is that it helps us create responsive web applications faster and easier. So the obvious question that comes to our mind is, what is a responsive web application? A responsive web application automatically adapts to different screen sizes (i.e desktop computers, laptops, tablets. mobile phones etc). A responsive application provides optimal viewing and interaction experience i.e easy reading and navigation with a minimum of resizing, panning, and scrolling across a wide range of devices. So you don't have to worry about your application not being compatible with multiple devices. The images at the following links shows how a responsive and non-responsive application looks like on a mobile device. At the following link is a live responsive application example. Notice as we resize the browser, the content automatically adpats to the screen size. Saves lot of development time : One of the biggest advantages of using Bootstrap is that it saves lot of development time. Instead of writing code from the scratch, bootstrap offers ready made blocks of code that you can use and customize to suit your application requirements. There are also many websites out there that offer free and paid Bootstrap themes that saves even more development time. Consistency : Bootstrap was developed by Twitter to encourage consistency across thier internal tools by giving their developers a centralised development code. Since all the developers are working using a centralised code, the end result is consistent regardless of who’s working on the project and which web browser is being used. Customizable : If you are using only a few features of bootstrap, you can customize to download only those features using the following bootstrap customize page. Support : As Bootstrap is the most popular framework, it has a very large community base and excellent documentation. Bootstrap's excellent documentation, examples and demos helps a developer learn bootstrap quickly even if you are new to it. If you ever run into an issue you will usually get help quickly and easily from the vast online community and web forums. In our next video we will discuss, downloading, setting up and understanding different bootstrap components. Please stay tuned. Link for all dot net and sql server video tutorial playlists Link for slides, code samples and text version of the video


In this part of the c sharp tutorial we will learn about interfaces Text version of the video Slides All C Text Articles All C Slides Complete C tutorial All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn about pivot operator. Pivot is a sql server operator that can be used to turn unique values from one column, into multiple columns in the output, there by effectively rotating a table. Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Link for code samples used in the demo Link for all dot net and sql server video tutorial playlists In this video, we will discuss 1. What is a windows service and how do they differe from regular applications and programs 2. How to view all the services installed on a windows machine 3. What is the use of windows services 4. When would an asp.net developer use a windows service What is a windows service and how do they differ from regular applications and programs A windows service is similar to any other program or application running on a windows machine. The following are the differences between a windows service and a regular application 1. Windows service runs in the background 2. They can be configured to start automatically when the system starts 3. They don't have user interface. How to view all the services installed on a windows machine 1. Open run windows by pressing Windows + R key 2. Type services.msc and press enter 3. The services window should display all the services installed on your computer What is the use of windows services Windows services provide core operating system features such as Event Logging - Windows Event Log Service Providing Security - Windows Firewall Service Error reporting - Windows Error Reporting Service When would an asp.net developer use a windows service In general, we should create a Windows Service to run code in the background all the time, without any sort of user interaction. An asp.net developer can use a windows service to host a wcf service. We can then configure the windows service to start automatically when the computer starts. This makes our WCF service always available for clients to consume, even if no-one is logged on, on that computer. In our next video, we will discuss, creating a windows service to host a WCF service


Text version of the video Slides All ASP.NET Text Articles All ASP.NET Slides ASP.NET Playlist All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic It is common for a web site to have a consistent look and behaviuor across all the pages in the web application. To have a common layout across all our pages, without the use of master pages. There are 2 options Option 1: Copy and paste the required HTML across all pages in the application The following are the problems with this approach 1. We have lot of duplicated HTML on every page 2. If we have to change something in the common layout, we will have to make the change in all the pages, which is time consuming and error prone. Option 2: Implement the layout using the following user controls. 1. Header user control 2. Menu user control 3. Footer user control The following are the problems with using user controls 1. We will end up with complicated HTML and CSS if we have to design the layout similar to the one in the above image 2. All the user controls have to be manually added on each and every page of the site So, the best approach to have a consistent look and feel across all pages in a web application is to use master pages. We will discuss master pages in our next video.


In this video we will learn about 1. Self Join - Joining a table with itself 2. Self Join is not a different type of join. It can be classified as Inner Self Join, Outer Self Join (Left, Right and Full), or Cross Self Join. Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


rank and dense_rank example difference between rank and dense_rank with example rank vs dense_rank in sql server 2008 sql server difference between rank and dense_rank In this video we will discuss Rank and Dense_Rank functions in SQL Server Rank and Dense_Rank functions Introduced in SQL Server 2005 Returns a rank starting at 1 based on the ordering of rows imposed by the ORDER BY clause ORDER BY clause is required PARTITION BY clause is optional When the data is partitioned, rank is reset to 1 when the partition changes Difference between Rank and Dense_Rank functions Rank function skips ranking(s) if there is a tie where as Dense_Rank will not. For example : If you have 2 rows at rank 1 and you have 5 rows in total. RANK() returns - 1, 1, 3, 4, 5 DENSE_RANK returns - 1, 1, 2, 3, 4 Syntax : RANK() OVER (ORDER BY Col1, Col2.) DENSE_RANK() OVER (ORDER BY Col1, Col2.) RANK() and DENSE_RANK() functions without PARTITION BY clause : In this example, data is not partitioned, so RANK() function provides a consecutive numbering except when there is a tie. Rank 2 is skipped as there are 2 rows at rank 1. The third row gets rank 3. DENSE_RANK() on the other hand will not skip ranks if there is a tie. The first 2 rows get rank 1. Third row gets rank 2. SELECT Name, Salary, Gender, RANK() OVER (ORDER BY Salary DESC) AS [Rank], DENSE_RANK() OVER (ORDER BY Salary DESC) AS DenseRank FROM Employees RANK() and DENSE_RANK() functions with PARTITION BY clause : Notice when the partition changes from Female to Male Rank is reset to 1 SELECT Name, Salary, Gender, RANK() OVER (PARTITION BY Gender ORDER BY Salary DESC) AS [Rank], DENSE_RANK() OVER (PARTITION BY Gender ORDER BY Salary DESC) AS DenseRank FROM Employees Use case for RANK and DENSE_RANK functions : Both these functions can be used to find Nth highest salary. However, which function to use depends on what you want to do when there is a tie. Let me explain with an example. If there are 2 employees with the FIRST highest salary, there are 2 different business cases 1. If your business case is, not to produce any result for the SECOND highest salary, then use RANK function 2. If your business case is to return the next Salary after the tied rows as the SECOND highest Salary, then use DENSE_RANK function Since we have 2 Employees with the FIRST highest salary. Rank() function will not return any rows for the SECOND highest Salary. WITH Result AS ( SELECT Salary, RANK() OVER (ORDER BY Salary DESC) AS Salary_Rank FROM Employees ) SELECT TOP 1 Salary FROM Result WHERE Salary_Rank = 2 Though we have 2 Employees with the FIRST highest salary. Dense_Rank() function returns, the next Salary after the tied rows as the SECOND highest Salary WITH Result AS ( SELECT Salary, DENSE_RANK() OVER (ORDER BY Salary DESC) AS Salary_Rank FROM Employees ) SELECT TOP 1 Salary FROM Result WHERE Salary_Rank = 2 You can also use RANK and DENSE_RANK functions to find the Nth highest Salary among Male or Female employee groups. The following query finds the 3rd highest salary amount paid among the Female employees group WITH Result AS ( SELECT Salary, Gender, DENSE_RANK() OVER (PARTITION BY Gender ORDER BY Salary DESC) AS Salary_Rank FROM Employees ) SELECT TOP 1 Salary FROM Result WHERE Salary_Rank = 3 AND Gender = 'Female' Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


difference between cube and rollup in sql server 2008 sql server rollup vs cube difference between cube and rollup in sql server 2005 rollup and cube in sql server 2005 In this video we will discuss the difference between cube and rollup in SQL Server. CUBE generates a result set that shows aggregates for all combinations of values in the selected columns, where as ROLLUP generates a result set that shows aggregates for a hierarchy of values in the selected columns. Let us understand this difference with an example. ROLLUP(Continent, Country, City) produces Sum of Salary for the following hierarchy Continent, Country, City Continent, Country, Continent () CUBE(Continent, Country, City) produces Sum of Salary for all the following column combinations Continent, Country, City Continent, Country, Continent, City Continent Country, City Country, City () SELECT Continent, Country, City, SUM(SaleAmount) AS TotalSales FROM Sales GROUP BY ROLLUP(Continent, Country, City) SELECT Continent, Country, City, SUM(SaleAmount) AS TotalSales FROM Sales GROUP BY CUBE(Continent, Country, City) You won't see any difference when you use ROLLUP and CUBE on a single column. Both the following queries produces the same output. SELECT Continent, Sum(SaleAmount) AS TotalSales FROM Sales GROUP BY ROLLUP(Continent) -- OR SELECT Continent, SUM(SaleAmount) AS TotalSales FROM Sales GROUP BY CUBE(Continent) Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


2 way data binding angularjs angularjs directive two way binding angularjs two way binding example ng-model directive example angularjs ng-model example In this video we will discuss, Two way databinding in AngularJS. Along the way we also discuss one of the very useful directive in angular ng-model. One of the most useful feature in AngularJS is the Two Way Data-Binding. The Two Way Data-Binding, keeps the model and the view in sync at all times, that is a change in the model updates the view and a change in the view updates the model. When the model changes the view is automatically updated. This is achieved using the data binding expression in the view. How about the other way round. How to keep the model up to date when the view changes. That's exactly is the purpose of ng-model directive. In the html below, notice the input element is decorated with ng-model directive. This ensures that whenever the value in the textbox is changed, angular will automatically update the message property of the $scope object. This means the ng-model directive automatically takes the form values and updates the model. The binding expression does the opposite, i.e whenever the model changes the view is automatically updated. Because of the two way data binding provided by angular, as you type in the textbox, the value is immediately displayed on the view just below the textbox. This two way binding feature provided by angular, eliminates the need to write any custom code to move data from the model to the view or from the view to the model. ng-model directive can be used with the following 3 html elements input select textarea Two way binding example with complex object is also discussed. Link for all dot net and sql server video tutorial playlists Link for slides, code samples and text version of the video


Link for code samples used in the demo Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists In this video, we will discuss HandleError attribute in asp.net mvc. HandleErrorAttribute is used to display friendly error pages to end user when there is an unhandled exception. Let us understand this with an example. Step 1: Create a blank asp.net mvc 4 application. Step 2: Add a HomeController. Copy and paste the following code. public ActionResult Index() throw new Exception( Something went wrong ); Notice that, the Index() action method throws an exception. As this exception is not handled, when you run the application, you will get the default yellow screen of death which does not make sense to the end user. Now, let us understand replacing this yellow screen of death, with a friendly error page. Step 3: Enable custom errors in web.config file, that is present in the root directory of your mvc application. customErrors element must be nested under [system.web] [customErrors mode= On ] [/customErrors] Step 4: Add Shared folder under Views folder. Add Error.cshtml view inside this folder. Paste the following HTML in Error.cdhtml view. [h2]An unknown problem has occured, please contact Admin[/h2] Run the application, and notice that, you are redirected to the friendly Error view, instead of the generic Yellow screen of death. We did not apply HandleError attribute anywhere. So how did all this work? HandleErrorAttribute is added to the GlobalFilters collection in global.asax. When a filter is added to the GlobalFilters collection, then it is applicable for all controllers and their action methods in the entire application. Right click on RegisterGlobalFilters() method in Global.asax, and select Go To Definition and you can find the code that adds HandleErrorAttribute to GlobalFilterCollection. public static void RegisterGlobalFilters(GlobalFilterCollection filters) filters.Add(new HandleErrorAttribute()); Is the friendly error page displayed for HTTP status code 404? No, but there is a way to display the friendly error page. In the HomeController, we do not have List() action method. So, if a user navigates to /Home/List, we get an error - The resource cannot be found. HTTP 404. To display a friendly error page in this case Step 1: Add ErrorController to controllers folder. Copy and paste the following code. public class ErrorController : Controller public ActionResult NotFound() return View(); Step 2: Right click on Shared folder and add NotFound.cshtml view. Copy and paste the following code. [h2]Please check the URL. The page you are looking for cannot be found[/h2] Step 3: Change customErrors element in web.config as shown below. [customErrors mode= On ] [error statusCode= 404 redirect= ~/Error/NotFound /] [/customErrors] Make sure to replace [ with LESSTHAN and ] with GREATERTHAN symbol.


In this video we will learn about 1. What are temporary tables 2. The 2 different types of temporary tables -- Local Temporary Tables and Global Temporary tables 3. Difference between local and global temp tables Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this part we will learn replacing hard coded logic using delegates Text version of the video Slides All C Text Articles All C Slides Complete C tutorial All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn about 1. What is a view 2. Creating example views 3. Advantages of using views Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn about Transaction ACID tests. A successful transaction must pass the ACID test, that is a transaction must be Atomic, Consistent, Isolated and Durable. Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn, how to use coalesce() function in sql server, with an example Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will discuss async and await keywords and their use with an example. Text version of the video Slides All C Text Articles All C Slides All C Videos All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Link for code samples used in the demo Link for all dot net and sql server video tutorial playlists When an exception occurs in a WCF service, the service serializes the exception into a SOAP fault, and then sends the SOAP fault to the client. By default unhandled exception details are not included in SOAP faults that are propagated to client applications for security reasons. Instead a generic SOAP fault is returned to the client. For debugging purpose, if you want to include exception details in SOAP faults, enable IncludeExceptionDetailInFaults setting. This can be done in 2 ways as shown below. 1. In the config file using service behavior configuration [behaviors] [serviceBehaviors] [behavior name= inculdeExceptionDetails ] [serviceDebug includeExceptionDetailInFaults= true /] [/behavior] [/serviceBehaviors] [/behaviors] 2. In code using ServiceBehavior attribute [ServiceBehavior(IncludeExceptionDetailInFaults=true)] public class CalculatorService : ICalculatorService public int Divide(int Numerator, int Denominator) return Numerator / Denominator; Frequently asked WCF interview questions What happens when an exception occurs in a WCF service? OR What is a SOAP fault? OR How are WCF service exceptions reported to client applications?


In this video we will learn about transaction processing in sql server. These concepts are applicable to sql server 2000, 2005 an 2008 Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this part of the c sharp tutorial we will learn about explicit interface implementation. Text version of the video Slides All C Text Articles All C Slides Complete C tutorial All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Link for all dot net and sql server video tutorial playlists Link for slides, code samples and text version of the video This is a very common SQL Server Interview Question. There are several ways of finding the nth highest salary. By the end of this video, we will be able to answer all the following questions as well. How to find nth highest salary in SQL Server using a Sub-Query How to find nth highest salary in SQL Server using a CTE How to find the 2nd, 3rd or 15th highest salary Let's use the following Employees table for this demo Use the following script to create Employees table Create table Employees ( ID int primary key identity, FirstName nvarchar(50), LastName nvarchar(50), Gender nvarchar(50), Salary int ) GO Insert into Employees values ('Ben', 'Hoskins', 'Male', 70000) Insert into Employees values ('Mark', 'Hastings', 'Male', 60000) Insert into Employees values ('Steve', 'Pound', 'Male', 45000) Insert into Employees values ('Ben', 'Hoskins', 'Male', 70000) Insert into Employees values ('Philip', 'Hastings', 'Male', 45000) Insert into Employees values ('Mary', 'Lambeth', 'Female', 30000) Insert into Employees values ('Valarie', 'Vikings', 'Female', 35000) Insert into Employees values ('John', 'Stanmore', 'Male', 80000) GO To find the highest salary it is straight forward. We can simply use the Max() function as shown below. Select Max(Salary) from Employees To get the second highest salary use a sub query along with Max() function as shown below. Select Max(Salary) from Employees where Salary [ (Select Max(Salary) from Employees) To find nth highest salary using Sub-Query SELECT TOP 1 SALARY FROM ( SELECT DISTINCT TOP N SALARY FROM EMPLOYEES ORDER BY SALARY DESC ) RESULT ORDER BY SALARY To find nth highest salary using CTE WITH RESULT AS ( SELECT SALARY, DENSE_RANK() OVER (ORDER BY SALARY DESC) AS DENSERANK FROM EMPLOYEES ) SELECT TOP 1 SALARY FROM RESULT WHERE DENSERANK = N To find 2nd highest salary we can use any of the above queries. Simple replace N with 2. Similarly, to find 3rd highest salary, simple replace N with 3. Please Note: On many of the websites, you may have seen that, the following query can be used to get the nth highest salary. The below query will only work if there are no duplicates. WITH RESULT AS ( SELECT SALARY, ROW_NUMBER() OVER (ORDER BY SALARY DESC) AS ROWNUMBER FROM EMPLOYEES ) SELECT SALARY FROM RESULT WHERE ROWNUMBER = 3


In this video we will learn 1. Retrieve the last generated identity column value 2. Difference between SCOPE_IDENTITY(), @@Identity and IDENT_CURRENT('TableName') Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


In this video we will learn about 1. The different types of Joins in sql server 2. Cross Join 3. Inner Join 4. Outer Join -- Left , Right and Full Outer Join. Text version of the video Slides All SQL Server Text Articles All SQL Server Slides All Dot Net and SQL Server Tutorials in English All Dot Net and SQL Server Tutorials in Arabic


Text version of the video Slides All ASP.NET Web API Text Articles and Slides All ASP.NET Web API Videos All Dot Net and SQL Server Playlists


Link for code samples used in the demo Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists When you create a new asp.net mvc application, the following folders are created with in the root directory. 1. Models 2. Views 3. Controllers This structure is fine for simple applications, but when your application gets big and complex, maintaining your Models, Views and Controllers can get complicated. The structure of a complex asp.net mvc application can be very easily maintained using areas. So, in short areas are introduced in asp.net mvc 2, that allow us to breakdown a large complex application into a several small sections called areas. These areas can have their own set of 1. Models 2. Views 3. Controllers 4. Routes Let's understand this with an example. Let's understand this with an example. Let's say, we are building a Job Portal. It's common for a typical job portal to have the following functional areas. Employee Area - This functional area allows a job seeker to create their profile, upload resume, and perform job search. Employer Area - This functional area allows a job provider to create employer profile, upload jobs, and search for suitable candidates. Administrator Area - This functional area allows an administrator to configure the site and mantain. To create an area in an MVC application 1. Right click on the project name in Solution Explorer and select Add =] Area 2. Provide a meaningful name. For example Employee and click Add At this point, Areas folder will be created, and with in this, a folder for Emploee area will be added. You can add as many areas as you want. In a similar fashion, add areas for Employer and Admin. Notice that in each area folder (Employee, Employer and Admin), you have a set of Models, Views and Controllers folders. Also, there is AreaRegistration.cs file, which contains the code to register a route for the area. Now navigate to Global.asax.cs file and notice Application_Start(). With in this method there is code to register all areas in your application. protected void Application_Start() AreaRegistration.RegisterAllAreas(); WebApiConfig.Register(GlobalConfiguration.Configuration); FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters); RouteConfig.RegisterRoutes(RouteTable.Routes); At this point Add HomeController to the following areas. Notice that we can have a HomeController(Controller with the same) in Employee, Employer, Admin and MainArea. 1. Employee 2. Employer 3. Admin 4. Main Area At this point, we have Index() action method in all of the HomeControllers. public ActionResult Index() return View(); Now Add Index view to all the areas. Copy and paste the following HTML in respective Index views. Main Area: [h1]Main Area Index View[/h1] Employee Area: [h1]Employee Area Index View[/h1] Employer Area: [h1]Employer Area Index View[/h1] Admin Area: [h1]Admin Area Index View[/h1] At this point, build the application, and navigate to /MVCDemo. You will get an error. To fix this change RegisterRoutes() method in RouteConfig.cs file in App_start folder. Notice that we are passing the namespace of the HomeController in the Main area using namespace parameter. public static void RegisterRoutes(RouteCollection routes) routes.IgnoreRoute( resource.axd/ *pathInfo ); routes.MapRoute( name: Default , url: controller / action / id , defaults: new controller = Home , action = Index , id = UrlParameter.Optional , namespaces: new [] MVCDemo.Controllers ); Now, if you navigate to /MVCDemo/Employee, you will get an error - The resource cannot be found. To fix this, change RegisterArea() area method in EmployeeAreaRegistration.cs file in Employee folder as shown below. Notice that we are setting HomeController as the default controller public override void RegisterArea(AreaRegistrationContext context) context.MapRoute( Employee_default , Employee/ controller / action / id , new controller = Home , action = Index , id = UrlParameter.Optional ); Navigating to may throw a compilation error related to System.Web.Optimization. If you get this error follow the steps below. 1. In Visual Studio, click Tools - Library PAckage Manager - Package Manager Console 2. In the Package Manager Console window, type the following command and press enter Install-Package Microsoft.Web.Optimization -Pre When we are building links using ActionLink() html helper to navigate between areas, we need to specify area name. once you do this, you will be able to navigate between areas when you click on the respective links.


Link for code samples used in the demo Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists What is Unobtrusive JavaScript? Unobtrusive JavaScript, is a JavaScript that is separated from the web site's html markup. There are several benefits of using Unobtrusive JavaScript. Separation of concerns i.e the HTML markup is now clean without any traces of javascript. Page load time is faster. It is also easy to update the code as all the Javascript logic is present in a separate file. We also get, better cache support, as all our JavaScript is now present in a separate file, it can be cached and accessed much faster.


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