Introduction to ADO.NET


Introduction

ADO: ActiveX Data Object
Provides access to the data sources like MS Access, SQL, Oracle, XML...
Root classes are found in the System.Data
XML integration is provided by System.Xml

Architecture

Connected Architecture
Disconnected Architecture: Read all data at a time and store it in the data set




To access databases such as SQL, Oracle, and MS Access in .NET Framework we have classes that behave as Data Providers in the System.Data namespace.

Classes such as:
Connection, Command (Insert, Update, Delete): Connected Architecture
Retrieving the data - DataReader: Connected Architecture
                                  Data Adapter: Disconnected Architecture

DataReader: Useful when we have a small amount of records to be retrieved from the DB. Whenever the SELECT statement is executed it will generate a result set in DB, and DataReader will every time go to the DB and read one data at a time. Round trip increase.

Data Adapter: Put all the data from a particular connection and fill a dataset (disconnected architecture). And continue accessing the data from time to time.


Here Data Providers are:
System.Data.SqlClient
System.Data.OracleClient
System.DataOleDb (Object Linking and Embedding): MS Access-like thing
System.Data.Odbc (Open Database Connectivity)

Each Data Providers will provide different classes like:
Connection,
Commands,
DataReader,
DataAdapter

Finally, a DataSet which keeps the data in Disconnected mode.

Disconnected Architecture:

It's a storage & management of data without connection
Data is stored in the client's machine
System.Data provides the required classes
DataTable, DataColumn, DataRow ... are a few common classes
Data is stored in tabular format only


DataSet:

It's a collection of data tables
DataAdapter gets the data from DB and fills the dataset
Relationships can be maintained
Can sync the database


Connected Architecture:

The connection class establishes the DB connection
Command class executes the commands (DML, DQL)
DataReader reads data one by one from the DB in a forward-only manner
DataAdaptor behaves as a bridge between connected and disconnected architecture






Executing Commands:













Popular posts from this blog

Introduction to Docker

Image
What is Docker? Docker is an open-source platform that allows developers to build, package, and deploy applications as containers while ensuring that they run consistently across different environments, Containers are lightweight and efficient units of software that bundle together all the necessary code, libraries, and dependencies required to run an application. Docker works by isolating an application and its dependencies into a container, which can then be run on any machine that has the Docker platform installed.  Docker containers are isolated from each other and from the host system, which helps to prevent conflicts between applications and ensures that the application runs consistently regardless of the underlying system. Docker uses a client-server architecture and comprises several components, including the Docker engine, Docker CLI, and Docker Hub, The Docker engine is responsible for building, running, and managing containers, Docker CLI provides a command-line interf...
Read more

SOLID Principles

Image
Introduced by Robert C.Martin , known as Uncle Bob A set of principles that must be followed to develop flexible, maintainable, and scalable software systems Helps in reducing ' Tight Coupling ': A group of classes is highly dependent on one another. Loosely coupled classes minimize code changes, making code more reusable, maintainable, and flexible. Single Responsibility Principle One class = One responsibility One class = One reason to change Problem: The Program  class violates the SRP as it handles three separate responsibilities: Main() , CalculateArea() , and Print() . Rectification: Open-Closed Principle Class must  open for extension , but closed for modification Problem:  When creating a new shape, such as a rectangle, calling CalculateArea() and Print() requires passing a rectangle parameter, but the current design does not allow it. Rectification:  Therefore, we need to extend the CalculateArea and Printer classes without modifying their existing meth...
Read more

Nuget package | Pushing it to Azure Artifacts

Image
NuGet is a package management tool for .NET development that makes it easy to create, share, and consume packages . NuGet pack:   used to create a NuGet package from the files in a project,  will create a .nupkg file that contains the compiled output of the project along with any dependencies that are required for the package to work correctly.  Note: We can customize the package metadata by including a .nuspec file in our project or by passing in arguments to the Nuget Pack command. NuGet push:   used to publish a NuGet package to a NuGet server.  NuGet will upload the .nupkg file to the specified NuGet server. Note:  We'll need to provide authentication credentials for the server in order to push a package. Here's an example of how we might use nuget pack and nuget push : Navigate to the directory that contains the project we want to package (.csproj). Run nuget pack to create a .nupkg file for the project, nuget pack MyProject.csproj If we want to c...
Read more

WiX - Windows Installer XML

Image
Many ways of generating MSI packages for Windows applications. E.g: Vdproj, WiX ·         WIX:  Windows Installer XML ·         Free software toolset ·         XML code structure ·         Supports command-line interface to be integrated into any automated application build process or CI environment. ·         Developed by Microsoft, using this to develop installation packages for all their major products, including Office and Visual Studio Bundle ·         Bundles are often used to install prerequisites, such as the .NET Framework or C++ Run Time ·         Bundles also allow very large applications to be broken into smaller, logical installation packages that are chained together while still presenting a single product to the end-user. WiX Component The W...
Read more

Working with Git

Image
Git States Basic Git Commands git remote -v [shows the remote repository URLs linked to your local repo] git clone "<repository_url>" git add . [add all new and modified files (excluding deleted files)] OR, git add -A [add all changes, including deleted files] git add <file> [add specific file] git status [shows the status of your working directory (tracked/untracked/staged changes)] git commit -m "Commit message here" git log [displays commit history (press q to quit log view)] git push Working with Branches git branch [shows local branches] git branch -r [shows remote branches] git branch -a [shows both local and remote branches] git branch  devfeaturebranch git checkout  devfeaturebranch OR, git checkout -b devfeaturebranch [create & switch] git push -u origin devfeaturebranch [first-time push when the branch is not present in the remote] OR, git push [for subsequent pushes] git branch -d featurebranch [delete locally, use -D for forcefully delet...
Read more

C# Memory Tricks: Learn How To Master The Garbage Collector

Image
Introduction to .NET memory management Heap: Whenever an object/variable is created using the new keyword, it's stored in the Heap section of memory. How to release the Heap memory? In some languages such as C++, we have the "delete" keyword to free dynamically allocated memory on the heap. But in the.NET Framework, we don't have such. Here we have the Garbage collector which continuously deletes objects that is no longer used for our code. But why has Microsoft did not implement the "delete" keyword? Disadvantages of Garbage collection Fundamentals of the .NET Framework The Stack: Block of memory that is used for calling methods and storing local variables. The Heap:  Value type:  If we have local variables of value type they will store in Stack along with value and type, like this:- int a  = 1234; int b = 0; ----------------- int b = a; Reference type:  Type of variable that refers to the value stored on the heap. Boxing and Unboxing: A detailed look at ...
Read more

gRPC - Protobuf / Protocol Buffers

Image
  Overview: Protobuf / Protocol Buffers   –  an interface definition language or interface description language ( IDL ). Protobuf is a great way for schema definition and auto-generating source code. It ensures type safety, faster serialization, and deserialization.  SOAP - XML REST - JSON gRPC - Protocol Buffer Problems With JSON: No strict schema enforcement. People can easily change the structure to break the contract and it can cause confusion among the team members. // team 1 expectation { "order_id" : 1234 } // team 2 understanding { "orderId" : 1234 } // team 3 understanding { "order" : { "id" : 1234 } } Copy JSON is text-based. Human-friendly but not machine friendly. It takes time to serialize and deserialize when we use it for microservices communication. Protobuf/ Protocol Buffers : Protobuf  is Google’s  language-neutral ,  platform-neutral  method for deserializing & serializing  s...
Read more

Custom Azure DevOps pipeline task extension

Image
Pre-requisites/Dependencies 1.         Azure DevOps Organization with project 2.         Node.js (ver 10.x or higher) & NPM ·         Node.js is required to run the Azure DevOps CLI tools. Installing Node.js will also install NPM (Node Package Manager), which is used to install other dependencies. ·         Download:  Here (accept the default options in the setup wizard)   3.         TFX CLI (Azure DevOps Extension Tool) ·         TFX CLI is used to create, package, and publish Azure DevOps extensions. ·         Install via NPM (use any terminal): npm install -g tfx-cli 4.         Visual Studio Code ·         Visual Studi...
Read more

C# Questions Part 1

Image
  1.  What is a class? A class is a template to create an object. It contains properties as well as methods. Whereas an  Object is a real-time entity, consisting of state (look & feel) and behavior (what it does) 1 2 3 4 5 6 7 8 9 10 11 12 public class Student {    //data members    public int rollNumber { get ; set ; }    public string fullName { get ; set ; }      //method    public void PrintDetails ( )    {        //code of method    } } 2.  What are the main concepts of OOPs? Encapsulation, abstraction, polymorphism,  and  inheritance  are the main concepts of object-oriented programming. 3. Explain Encapsulation Encapsulation  is a  process of wrapping functions  and data members together in a class. It is like a  capsule , a single unit. Encapsulation is to prevent the unauthorized or unwanted chang...
Read more