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Part 33 - C# Tutorial - Difference between abstract classes and interfaces.avi
 
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Text version of the video http://csharp-video-tutorials.blogspot.com/2012/06/part-33-c-tutorial-difference-between.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-33-abstract-classes-vs-interfaces.html All C# Text Articles http://csharp-video-tutorials.blogspot.co.uk/p/free-c-video-tutorial-for-beginners.html All C# Slides http://csharp-video-tutorials.blogspot.com/p/c.html Complete C# tutorial https://www.youtube.com/playlist?list=PLAC325451207E3105 All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists In this part of the c sharp tutorial we will learn about the differences between abstract classes and interfaces
Views: 308649 kudvenkat
Cross apply and outer apply in sql server
 
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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 http://csharp-video-tutorials.blogspot.com/2015/09/cross-apply-and-outer-apply-in-sql.html Slides http://csharp-video-tutorials.blogspot.com/2015/09/cross-apply-and-outer-apply-in-sql_8.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 67322 kudvenkat
Closures in JavaScript
 
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Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2014/12/closures-in-javascript.html 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);
Views: 76892 kudvenkat
Part 68   What is the use of NonAction attribute in mvc
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/08/part-68-what-is-use-of-nonaction.html Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists In this video, we will discuss the use of NonAction attribute in asp.net mvc The following questions could be asked in an interview What is the use of NonAction attribute in MVC? OR How do you restrict access to public methods in a controller? An action method is a public method in a controller that can be invoked using a URL. So, by default, if you have any public method in a controller then it can be invoked using a URL request. To restrict access to public methods in a controller, NonAction attribute can be used. Let's understand this with an example. We have 2 public methods in HomeController, Method1() and Method2(). Method1 can be invoked using URL /Home/Method1 Method2 can be invoked using URL /Home/Method2 public class HomeController : Controller { public string Method1() { return "[h1]Method 1 Invoked[/h1]"; } public string Method2() { return "[h1]Method 2 Invoked[/h1]"; } } Let's say Method2() is for doing some internal work, and we don't want it to be invoked using a URL request. To achieve this, decorate Method2() with NonAction attribute. [NonAction] public string Method2() { return "[h1]Method 2 Invoked[/h1]"; } Now, if you naviage to URL /Home/Method2, you will get an error - The resource cannot be found. Another way to restrict access to methods in a controller, is by making them private. private string Method2() { return "[h1]Method 2 Invoked[/h1]"; } In general, it's a bad design to have a public method in a controller that is not an action method. If you have any such method for performing business calculations, it should be somewhere in the model and not in the controller. However, if for some reason, if you want to have public methods in a controller and you don't want to treat them as actions, then use NonAction attribute. Make sure to replace [ with LESSTHAN and ] with GREATERTHAN symbol.
Views: 50831 kudvenkat
Indexes in sql server   Part 35
 
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In this video we will learn about What are indexes Why do we use indexes Advantages of indexes These concepts are applicable to sql server 2000, 2005 and 2008 Text version of the video http://csharp-video-tutorials.blogspot.com/2012/09/indexes-in-sql-server-part-35.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-35-indexes.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 348928 kudvenkat
Difference between blocking and deadlocking
 
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deadlock vs blocking sql server In this video we will discuss the difference between blocking and deadlocking. This is one of the common SQL Server interview question. Let us understand the difference with an example. 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 Blocking : Occurs if a transaction tries to acquire an incompatible lock on a resource that another transaction has already locked. The blocked transaction remains blocked until the blocking transaction releases the lock. Example : 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. Notice that Transaction 2 is blocked by Transaction 1. Transaction 2 is allowed to move forward only when Transaction 1 completes. --Transaction 1 Begin Tran Update TableA set Name='Mark Transaction 1' where Id = 1 Waitfor Delay '00:00:10' Commit Transaction --Transaction 2 Begin Tran Update TableA set Name='Mark Transaction 2' where Id = 1 Commit Transaction Deadlock : Occurs when two or more transactions have a resource locked, and each transaction requests a lock on the resource that another transaction has already locked. Neither of the transactions here can move forward, as each one is waiting for the other to release the lock. So in this case, SQL Server intervenes and ends the deadlock by cancelling one of the transactions, so the other transaction can move forward. Example : 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. Notice that there is a deadlock between Transaction 1 and Transaction 2. -- 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 Link for all dot net and sql server video tutorial playlists https://www.youtube.com/user/kudvenkat/playlists?sort=dd&view=1 Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2015/09/difference-between-blocking-and.html
Views: 65927 kudvenkat
Part 32 - C# Tutorial - Abstract classes in c#.avi
 
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In this part of the c sharp tutorial we will learn about abstract classes Text version of the video http://csharp-video-tutorials.blogspot.com/2012/06/part-32-c-tutorial-abstract-classes.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-32-abstract-classes.html All C# Text Articles http://csharp-video-tutorials.blogspot.co.uk/p/free-c-video-tutorial-for-beginners.html All C# Slides http://csharp-video-tutorials.blogspot.com/p/c.html Complete C# tutorial https://www.youtube.com/playlist?list=PLAC325451207E3105 All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 266907 kudvenkat
Part 6  ViewData and ViewBag in mvc
 
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Text version of the video http://csharp-video-tutorials.blogspot.com/2013/04/part-6-viewdata-and-viewbag-in-mvc.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-6-view-data-and-view-bag-in-mvc.html All ASP .NET MVC Text Articles http://csharp-video-tutorials.blogspot.com/p/aspnet-mvc-tutorial-for-beginners.html All ASP .NET MVC Slides http://csharp-video-tutorials.blogspot.com/p/aspnet-mvc-slides.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists In this video we will discuss 1. What is ViewData 2. What is ViewBag 3. Difference between ViewData and ViewBag Both ViewData and ViewBag are used to pass data from a controller to a view. ViewData is a dictionary of objects that are stored and retrieved using strings as keys. The syntax of ViewData is very similar to that of ViewState, SessionState and ApplicationState. // Storing data in ViewData ViewData["YourData"] = "SomeData"; // Retrieving data from ViewData string strData = ViewData["YourData"].ToString(); ViewData does not provide compile time error checking. For example, if you mis-spell the key names you wouldn't get any compile time error. You get to know about the error only at runtime. ViewBag uses the dynamic feature that was introduced in to C# 4. It allows an object to have properties dynamically added to it. Using ViewBag the above code can be rewritten as below. // Storing data in ViewBag ViewBag.YourData = "SomeData"; // Retrieving data from ViewBag string strData = ViewBag.YourData; Just like ViewData, ViewBag does not provide compile time error checking. For example, if you mis-spell the property name, you wouldn't get any compile time error. You get to know about the error only at runtime. Internally ViewBag properties are stored as name/value pairs in the ViewData dictionary. Please Note: To pass data from controller to a view, It's always a good practice to use strongly typed view models instead of using ViewBag & ViewData. Strongly typed view models provide compile time error checking. We will discuss view models in a later video session.
Views: 422764 kudvenkat
Part 1   Introduction to WCF
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/11/part-1-introduction-to-wcf.html Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/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.
Views: 724426 kudvenkat
Difference between where and having in sql server
 
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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 http://csharp-video-tutorials.blogspot.com/2015/09/difference-between-where-and-having-in.html Slides http://csharp-video-tutorials.blogspot.com/2015/09/difference-between-where-and-having-in_15.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html Full SQL Server Course https://www.youtube.com/playlist?list=PL4cyC4G0M1RQ_Rm52cQ4CcOJ_T_HXeMB4 All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 61840 kudvenkat
Clustered and nonclustered indexes in sql server   Part 36
 
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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 http://csharp-video-tutorials.blogspot.co.uk/2012/09/clustered-and-non-clustered-indexes.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-36-clustered-nonclustered-indexes.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 429246 kudvenkat
Database normalization   Part 52
 
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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 http://csharp-video-tutorials.blogspot.com/2012/09/database-normalization-part-52.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-52-normalization.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 174068 kudvenkat
Part 71   childactiononly attribute in mvc
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/08/part-71-childactiononly-attribute-in-mvc.html Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists In this video, we will discuss childactiononly attribute in asp.net mvc. Let us understand this with an example. Step 1: Create a blank asp.net mvc 4 application Step 2: Add HomeController. Copy and paste the following code. public class HomeController : Controller { // Public action method that can be invoked using a URL request public ActionResult Index() { return View(); } // This method is accessible only by a child request. A runtime // exception will be thrown if a URL request is made to this method [ChildActionOnly] public ActionResult Countries(List[String] countryData) { return View(countryData); } } Step 3: Right click on the "Countries()" action method and add "Countries" view. This view will render the given list of strings as an un-ordered list. @model List[string] @foreach (string country in Model) { [ul] [li] [b] @country [/b] [/li] [/ul] } Step 4: Right click on the "Index()" action method and add "Index" view. Copy and paste the following code. Notice that, to invoke childaction, we are using Action() HTML Helper. [h2]Countries List[/h2] @Html.Action("Countries", new { countryData = new List[string]() { "US", "UK", "India" } }) Please Note: Child actions can also be invoked using "RenderAction()" HTMl helper as shown below. @{ Html.RenderAction("Countries", new { countryData = new List[string]() { "US", "UK", "India" } }); } We discussed the difference between Action() and RenderAction() in Part XX of MVC Tutorial series. Points to remember about "ChildActionOnly" attribute 1. Any action method that is decorated with [ChildActionOnly] attribute is a child action method. 2. Child action methods will not respond to URL requests. If an attempt is made, a runtime error will be thrown stating - Child action is accessible only by a child request. 3. Child action methods can be invoked by making child request from a view using "Action()" and "RenderAction()" html helpers. 4. An action method doesn't need to have [ChildActionOnly] attribute to be used as a child action, but use this attribute to prevent if you want to prevent the action method from being invoked as a result of a user request. 5. Child actions are typically associated with partial views, although this is not compulsory. 6. Child action methods are different from NonAction methods, in that NonAction methods cannot be invoked using Action() or RenderAction() helpers. We discussed NonAction methods in Part 70 of ASP.NET MVC tutorial series. 7. Using child action methods, it is possible to cache portions of a view. This is the main advantage of child action methods. We will cover this when we discuss [OutputCache] attribute. Make sure to replace [ with LESSTHAN and ] with GREATERTHAN symbol.
Views: 77202 kudvenkat
C# abstract class virtual method
 
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Text version of the video http://csharp-video-tutorials.blogspot.com/2016/10/c-abstract-class-virtual-method.html Slides http://csharp-video-tutorials.blogspot.com/2016/10/c-abstract-class-virtual-method_24.html All C# Interview Questions Text Articles & Slides http://csharp-video-tutorials.blogspot.com/p/c-interview-questions.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 53239 kudvenkat
Correlated subquery in sql   Part 60
 
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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 http://csharp-video-tutorials.blogspot.com/2013/01/correlated-subquery-in-sql-part-60.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-60-co-related-subqueries.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 119422 kudvenkat
Part 3   Why and when should we use an abstract class
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/09/part-3-why-and-when-should-we-use.html Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists This question can also be asked in a slightly different way Give an example of where we could use an abstract class? Let us understand when to use an abstract class with an example. An organisation has 2 types of employees 1. FullTimeEmployee 2. ContractEmployee We would create an abstract class, when want to move the common functionality of 2 or more related classes into a base class and when, we don't want that base class to be instantiated.
Views: 461695 kudvenkat
FIRST VALUE function in SQL Server
 
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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 http://csharp-video-tutorials.blogspot.com/2015/10/firstvalue-function-in-sql-server.html Slides http://csharp-video-tutorials.blogspot.com/2015/10/firstvalue-function-in-sql-server_6.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
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Part 146   Why use master pages in asp net
 
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Text version of the video http://csharp-video-tutorials.blogspot.com/2013/10/part-146-why-use-master-pages-in-aspnet.html Slides http://csharp-video-tutorials.blogspot.com/2013/11/part-146-why-use-master-pages-in-aspnet.html All ASP .NET Text Articles http://csharp-video-tutorials.blogspot.com/p/free-aspnet-video-tutorial.html All ASP .NET Slides http://csharp-video-tutorials.blogspot.com/p/aspnet-slides.html ASP.NET Playlist https://www.youtube.com/playlist?list=PL4cyC4G0M1RQcB4IYS_zwkyBwMyx5AnDM All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists 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.
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Lead and Lag functions in SQL Server 2012
 
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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 http://csharp-video-tutorials.blogspot.com/2015/10/lead-and-lag-functions-in-sql-server.html Slides http://csharp-video-tutorials.blogspot.com/2015/10/lead-and-lag-functions-in-sql-server_5.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 45410 kudvenkat
Difference between AngularJS, Angular 2 and Angular 4
 
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Text version of the video http://csharp-video-tutorials.blogspot.com/2017/09/difference-between-angularjs-angular-2.html Slides http://csharp-video-tutorials.blogspot.com/2017/09/difference-between-angularjs-angular-2_13.html Angular 2 Tutorial playlist https://www.youtube.com/playlist?list=PL6n9fhu94yhWqGD8BuKuX-VTKqlNBj-m6 Angular 2 Text articles and slides http://csharp-video-tutorials.blogspot.com/2017/06/angular-2-tutorial-for-beginners_12.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists 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
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AngularJS tutorial -  What is AngularJS
 
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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, https://www.madewithangular.com, 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 https://angularjs.org. 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 https://angularjs.org. 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 https://www.youtube.com/user/kudvenkat/playlists?sort=dd&view=1 Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2015/10/what-is-angularjs.html
Views: 1594935 kudvenkat
Part 22 - C# Tutorial - Method hiding in c#.avi
 
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Text version of the video http://csharp-video-tutorials.blogspot.com/2012/06/part-22-c-tutorial-method-hiding-in-c.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-22-method-hiding-in-c.html All C# Text Articles http://csharp-video-tutorials.blogspot.co.uk/p/free-c-video-tutorial-for-beginners.html All C# Slides http://csharp-video-tutorials.blogspot.com/p/c.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists In this part of the c sharp tutorial we will learn 1. Method hiding 2. Invoke hidden base class members
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Group by in sql server - Part 11
 
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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 http://csharp-video-tutorials.blogspot.com/2012/08/group-by-part-11.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-11-group-by.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 401241 kudvenkat
Derived tables and common table expressions in sql server   Part 48
 
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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 http://csharp-video-tutorials.blogspot.com/2012/09/derived-table-and-cte-in-sql-server.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-48-derived-tables-cte.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
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Part 10   What happens if finally block throws an exception
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/10/part-10-what-happens-if-finally-block.html Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/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"); } } }
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What is bootstrap
 
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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. http://www.webnersolutions.com/wp-content/uploads/2015/08/responsive-vs-non-responsive-web-design1.jpg At the following link is a live responsive application example. Notice as we resize the browser, the content automatically adpats to the screen size. http://bootstrapdocs.com/v3.0.3/docs/examples/jumbotron/ 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. http://getbootstrap.com/customize/ 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 https://www.youtube.com/user/kudvenkat/playlists?sort=dd&view=1 Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2016/05/what-is-bootstrap.html
Views: 488162 kudvenkat
Part 30 - C# Tutorial - Interfaces in c#.avi
 
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In this part of the c sharp tutorial we will learn about interfaces Text version of the video http://csharp-video-tutorials.blogspot.com/2012/06/part-30-c-tutorial-interfaces-in-c.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-30-introduction-to-interfaces.html All C# Text Articles http://csharp-video-tutorials.blogspot.co.uk/p/free-c-video-tutorial-for-beginners.html All C# Slides http://csharp-video-tutorials.blogspot.com/p/c.html Complete C# tutorial https://www.youtube.com/playlist?list=PLAC325451207E3105 All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 417493 kudvenkat
Part 26   What is a windows service
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2014/02/part-26-what-is-windows-service_8.html Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/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
Views: 74178 kudvenkat
Part 60 C# Tutorial Difference between String and StringBuilder
 
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Tags string stringbuilder performance system.text.stringbuilder performance advantage of using system.text.stringbuilder over system.string stringbuilder namespace in c# stringbuilder append method c# stringbuilder append function convert stringbuilder object to string when to use stringbuilder over string stringbuilder vs string concatenation c# performance c# string concatenation best practice c# stringbuilder vs string concatenation string manipulation c# In this video we will understand the difference between System.String and System.Text.StringBuilder classes. We will also understand the difference between the terms mutable and immutable strings. C#, SQL Server, WCF, MVC and ASP .NET video tutorials for beginners https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd My Blog: www.csharp-video-tutorials.blogspot.com
Views: 104962 kudvenkat
Pivot in sql server 2008   Part 54
 
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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 http://csharp-video-tutorials.blogspot.com/2012/10/pivot-operator-in-sql-server-part-54.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-54-pivot-in-sql-server-2008.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 169843 kudvenkat
Rank and Dense Rank in SQL Server
 
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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 http://csharp-video-tutorials.blogspot.com/2015/10/rank-and-denserank-in-sql-server.html Slides http://csharp-video-tutorials.blogspot.com/2015/10/rank-and-denserank-in-sql-server_1.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 67668 kudvenkat
Self join in sql server - Part 14
 
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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 http://csharp-video-tutorials.blogspot.com/2012/08/self-join-in-sql-server-part-14.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-14-self-join.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 324220 kudvenkat
Union and union all in sql server   Part 17
 
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In this video we will learn about the 1. Purpose of UNION and UNION ALL 2. Difference between UNION and UNION ALL 3. Difference between JOIN and UNION Text version of the video http://csharp-video-tutorials.blogspot.com/2012/08/union-and-union-all-in-sql-server-part.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-17-union-and-union-all.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 242005 kudvenkat
Part 72   HandleError attribute in mvc
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/08/part-72-handleerror-attribute-in-mvc.html Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/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.
Views: 93564 kudvenkat
Part 15   Exception handling in WCF
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/12/part-15-exception-handling-in-wcf_5.html Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/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?
Views: 70929 kudvenkat
Transactions in sql server and ACID Tests   Part 58
 
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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 http://csharp-video-tutorials.blogspot.com/2012/10/transaction-acid-tests-part-58.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-58-transaction-acid-test.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 105127 kudvenkat
Views in sql server   Part 39
 
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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 http://csharp-video-tutorials.blogspot.com/2012/09/views-in-sql-server-part-39.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-39-views-in-sql-server.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 270311 kudvenkat
Stored procedures in sql server   Part 18
 
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In this video we will learn 1. What is a stored procedure 2. Stored Procedure example 3. Creating a stored procedure with parameters 4. Altering SP 5. Viewing the text of the SP 6. Dropping the SP 7. Encrypting stored procedure Text version of the video http://csharp-video-tutorials.blogspot.com/2012/08/stored-procedures-part-18.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-18-stored-procedures.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 682393 kudvenkat
Async and await in C# example
 
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In this video we will discuss async and await keywords and their use with an example. Text version of the video http://csharp-video-tutorials.blogspot.com/2016/10/async-and-await-in-c-example.html Slides http://csharp-video-tutorials.blogspot.com/2016/10/async-and-await-in-c-example_31.html All C# Text Articles http://csharp-video-tutorials.blogspot.com/p/free-c-video-tutorial-for-beginners.html All C# Slides http://csharp-video-tutorials.blogspot.com/p/c.html All C# Videos https://www.youtube.com/playlist?list=PLAC325451207E3105 All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 156775 kudvenkat
Two way databinding in AngularJS
 
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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 https://www.youtube.com/user/kudvenkat/playlists?sort=dd&view=1 Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2015/11/two-way-databinding-in-angularjs_3.html
Views: 370205 kudvenkat
Part 38 - C# Tutorial - Delegates usage in c# continued.avi
 
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In this part we will learn replacing hard coded logic using delegates Text version of the video http://csharp-video-tutorials.blogspot.com/2012/06/part-38-c-tutorial-delegates-example-ii.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-38-delegates-usage-in-c-ii.html All C# Text Articles http://csharp-video-tutorials.blogspot.co.uk/p/free-c-video-tutorial-for-beginners.html All C# Slides http://csharp-video-tutorials.blogspot.com/p/c.html Complete C# tutorial https://www.youtube.com/playlist?list=PLAC325451207E3105 All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 251791 kudvenkat
Coalesce function in sql server   Part 16
 
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In this video we will learn, how to use coalesce() function in sql server, with an example Text version of the video http://csharp-video-tutorials.blogspot.com/2012/08/coalesce-function-in-sql-server-part-16.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-16-coalesce-function-in-sql-server.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 214416 kudvenkat
Indexed views in sql server   Part 41
 
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In this video we will learn about, creating indexed views. A unique clustered index, is the first index that should be created on a view. Indexed views are also called as materialized views Text version of the video http://csharp-video-tutorials.blogspot.com/2012/09/indexed-views-in-sql-server-part-41.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-41-indexed-views.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 144156 kudvenkat
Part 1   How to find nth highest salary in sql
 
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Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2014/05/part-1-how-to-find-nth-highest-salary_17.html 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
Views: 804761 kudvenkat
Prototype in JavaScript
 
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Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2015/02/prototype-in-javascript.html 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
Views: 69562 kudvenkat
Transactions in sql server   Part 57
 
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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 http://csharp-video-tutorials.blogspot.com/2012/10/transactions-in-sql-server-part-57.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-57-transactions-in-sql-server.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 145780 kudvenkat
Part 87   What is Unobtrusive JavaScript
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/09/part-87-what-is-unobtrusive-javascript.html Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/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.
Views: 55140 kudvenkat
How to get the last generated identity column value in SQL Server - Part 8
 
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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 http://csharp-video-tutorials.blogspot.com/2012/08/how-to-get-last-generated-identity.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-8-retrieving-identity-column-values.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 303572 kudvenkat
Part 51   Advantages of using strongly typed views
 
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Link for code samples used in the demo http://csharp-video-tutorials.blogspot.com/2013/07/part-51-advantages-of-using-strongly.html Link for csharp, asp.net, ado.net, dotnet basics, mvc and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Make sure to replace [ with LESSTHAN and ] with GREATERTHAN symbol. There are several ways available to pass data from a controller to a view in an mvc application. 1. ViewBag or ViewData 2. Dynamic type 3. Strongly typed view The following are the advantages of using strongly typed views. We get 1. Intellisense and 2. Compile-time error checking With ViewBag and Dynamic type, we don't have these advantages. Using ViewBag: Notice that, the employee object is stored in ViewBag. In HomeController.cs public ActionResult Details(int id) { SampleDBContext db = new SampleDBContext(); Employee employee = db.Employees.Single(x =] x.Id == id); ViewBag.EmployeeData = employee; return View(); } We want to display employee FullName and Gender. Notice that, as we are typing FullName and Gender properties, we don't get intellisense. Also, if we mis-spell FullName or Gender properties, we will not get any compilation errors. We will come to know about these errors only at runtime. In Details.cshtml View [div class="display-label"] @Html.DisplayName("FullName") [/div] [div class="display-field"] @ViewBag.EmployeeData.FullName [/div] [div class="display-label"] @Html.DisplayName("Gender") [/div] [div class="display-field"] @ViewBag.EmployeeData.Gender [/div] Using Dynamic Type: In HomeController.cs public ActionResult Details(int id) { SampleDBContext db = new SampleDBContext(); Employee employee = db.Employees.Single(x =] x.Id == id); return View(employee); } In Details.cshtml View @model dynamic [div class="display-label"] @Html.DisplayName("FullName") [/div] [div class="display-field"] @Model.FullName [/div] [div class="display-label"] @Html.DisplayName("Gender") [/div] [div class="display-field"] @Model.Gender [/div] With dynamic type also, we don't get intellisense and compile-time error checking. Using Strongly Typed View: No change is required in the controller action method. Make the following change to Details.cshtml view. Notice that the view is strongly typed against Employee model class. We get intellisense and if we mis-spell a property name, we get to know about it at compile time. @model MVCDemo.Models.Employee [div class="display-label"] @Html.DisplayName("FullName") [/div] [div class="display-field"] @Model.FullName [div] [div class="display-label"] @Html.DisplayName("Gender") [/div] [div class="display-field"] @Model.Gender [/div] Please Note: We discussed enabling compile time error checking in views in Part 50 of the MVC tutorial.
Views: 66238 kudvenkat
Angular component lifecycle hooks
 
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Text version of the video http://csharp-video-tutorials.blogspot.com/2017/08/angular-component-lifecycle-hooks.html Slides http://csharp-video-tutorials.blogspot.com/2017/08/angular-component-lifecycle-hooks_1.html Angular 2 Tutorial playlist https://www.youtube.com/playlist?list=PL6n9fhu94yhWqGD8BuKuX-VTKqlNBj-m6 Angular 2 Text articles and slides http://csharp-video-tutorials.blogspot.com/2017/06/angular-2-tutorial-for-beginners_12.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists In this video we will discuss Angular component lifecycle hooks. A component has a lifecycle managed by Angular. Angular 1. Creates the component 2. Renders the component 3. Creates and renders the component children 4. Checks when the component data-bound properties change, and 5. Destroys the component before removing it from the DOM To tap into and react when these life cycle events occur, angular offers several lifecycle hooks The 3 most commonly used hooks are ngOnChanges - Executes, every time the value of an input property changes. The hook method receives a SimpleChanges object containing current and previous property values. This is called before ngOnInit. ngOnInit - Executes after the constructor and after ngOnChange hook for the first time. It is most commonly used for component initialisation and retrieving data from a database. ngOnDestroy - Executes just before angular destroys the component and generally used for performing cleanup. There are 3 simple steps to use the Life Cycle Hooks Step 1 : Import the Life Cycle Hook interface. For example, to use ngOnInit() life cycle hook, import OnInit interface. import { OnInit } from '@angular/core'; Step 2 : Make the component class implement the Life Cycle Hook interface, using the implements keyword as shown below. This step is optional, but good to have so you will get editor support and flags errors at compile time if you incorrectly implement the interface method or make any typographical errors. export class SimpleComponent implements OnInit { } Step 3 : Write the implementation code for the life cycle interface method. Each interface has a single hook method whose name is the interface name prefixed with ng. ngOnInit() { console.log('OnInit Life Cycle Hook'); } Let's understand ngOnChanges life cycle hook with a simple example. Here is what we want to do. As soon as the user starts typing into the text box, we want to capture the current and previous value and log it to the browser console. We can very easily achieve this by using the ngOnChanges life cycle hook. ngOnChanges, is called every time the value of an input property of a component changes. So first let's create a SimpleComponent with an input property as shown below. We will continue with the example we worked with in our previous video. Add a new folder in the App folder and name it Others. Add a new TypeScript file to this folder and name it - simple.component.ts. Copy and paste the following code which is commented and self explanatory. // Step 1 : Import OnChanges and SimpleChanges import { Component, Input, OnChanges, SimpleChanges } from '@angular/core'; // The selector "simple" will be used as the directive // where we want to use this component. Notice we are // also using the simpleInput property with interpolation // to display the value it receives from the parent // component @Component({ selector: 'simple', template: `You entered : {{simpleInput}}` }) // Step 2 : Implement OnChanges Life Cycle Hook interface export class SimpleComponent implements OnChanges { // Input property. As and when this property changes // ngOnChanges life cycle hook method is called @Input() simpleInput: string; // Step 3 : Implementation for the hook method // This code logs the current and previous value // to the console. ngOnChanges(changes: SimpleChanges) { for (let propertyName in changes) { let change = changes[propertyName]; let current = JSON.stringify(change.currentValue); let previous = JSON.stringify(change.previousValue); console.log(propertyName + ': currentValue = ' + current + ', previousValue = ' + previous); // The above line can be rewritten using // placeholder syntax as shown below // console.log(`${propertyName}: currentValue // = ${current }, previousValue = ${previous }`); } } }
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