cassandra vs rdbms data model

If you are coming from a relational database world like me then the initial terminology used in cassandra will be a bit confusing. I'll state some keywords which are used in cassandra and try to draw parallels of them to the relational world. Note: These parallels are just for ease of understanding...

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Cannot read remote side has closed Thrift Cassandra C#

I was seeing this error ("Cannot read remote side has closed") while trying to get Thrift API to work with Cassandra using Csharp. For the life of me I couldn't figure out what was wrong as even though the error is saying something like "Hey I think your Thrift server is down". That was not the case...

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SQL GROUP BY Example

The GROUP BY clause causes data in a table (or any data source) to be divided into groups based on the expressions (or conditions) given in the GROUP BY clause. Seems confusing? Probably.. Let's see what it means, Say you have Column1, Column 2..etc on your table. Now you say GROUP BY Column1 , what...

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ASP.Net Webforms Inline tags and code blocks

There are many elements inside a webforms (.aspx) page. To somebody beginning asp.net webforms these may seem quite similar and be confusing at first. (Well it was for me when I started learning asp.net webforms) So hopefully this might help another soul. Elements of a asp.net page (Inline tags and...

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DataContract vs Serializable WCF

When applied to a class Serializable attribute serializes everything inside of it including private fields thus the developer has no control as what to expose. When DataContract attribute is applied to a class it will serialize only the elements decorated with DataMember attribute thus the developer...

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ServiceContract Name property WCF

This property can give your contract a name which is different from the actual interface name. So this way if you decide to change the interface name of a already running WCF service your client wont break. Ex:  [ServiceContract(Name="IGoodbyeService")]     public interface IHelloService  ...

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Basic Elements of WCF Appconfig

All config items should be inside , <system.serviceModel> This is the WCF namespace provided by Microsoft. Inside the <system.serviceModel> element you have the <services> element. This is where you configure all your services. For each service you have a <service>...

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system.web vs system.webserver

I have not worked in IIS6 and mostly I have worked on IIS 7+ and this came up when I was following a very old article (2003) ASP.Net article. Anyway system.web is IIS6 and classic mode. system.webserver is IIS7+  and integrated mode. One scenario you might come across is when adding httpmodules...

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SQL JOIN Example

Joins can be quite perplexing initially hopefully this simple example will help.  Joins are used to combine data from multiple tables (usually two tables) There are three types of joins, 1. INNER 2. OUTER - FULL, LEFT, RIGHT 3. CROSS For all examples I'll be using the below given...

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SQL COUNT Example

COUNT returns the number of rows in a select statement (Also note that it doesn't consider null values), Note : I'll be using the AdventureWorks2008R2 sample database which can be downloaded from here, http://msftdbprodsamples.codeplex.com/releases/view/59211 Example 1, /* By using the * we return...

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DDL vs DML in SQL Server

DDL Data Definition Language (DDL) statements are used to define the database structure or schema. Examples: CREATE - to create objects in the database ALTER - alters the structure of the database DROP - delete objects from the database DML Data Manipulation Language (DML)...

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SQL Server Data Types

Here are the SQL server data types for quick reference, Exact numerics – (bigint, bit, decimal, int, money, numeric, smallint) Approximate numerics (float, real) Date and time (date, datetime2, datetime, datetimeoffset, time) Character strings (char, varchar, text) Unicode character strings (nchar,...

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ASP.NET ViewState example

ViewState is a client side state management mechanism. It is not the only state management mechanism. Some other examples would be, For client side state management, ·         Hidden Field ·         Cookies ·         Control...

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Could not load file or assembly EntityFramework, Version=6.0.0.0 and MVC 4

In MVC 4 this mostly happens when you create a MVC 4 project and then for your DAL (Data access layer ) you have a separate class library project and install EF through NuGet. NuGet will give you the latest version which is currently EF 6. When you try to run the project you will see an error similar...

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ViewBag vs ViewData in ASP.NET MVC

Bottom line is that they are essentially the same, ViewBag is just a dynamic wrapper around ViewData. ViewData is actually a dictionary used to pass data from controllers to views. The following example will make this clear, ViewBag.Name = "Padmika" is equal to, ViewData["Name"] = "Padmi...

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Browser definition safari3plus not found : Blackberry redirection not working

One of the clients of the product that I work on had a problem where a redirection to an apps download page was not working on Blackberry 6.0 and Blackberry 7.0 OS  devices and was working fine for BB 5.0 OS. Strangely this was working fine until the client had installed some updates from Microsoft. When...

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