diff --git a/PacticeSolution/MSSQL_MVVM_Sample/App.xaml b/PacticeSolution/MSSQL_MVVM_Sample/App.xaml
new file mode 100644
index 0000000..7364a49
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/App.xaml
@@ -0,0 +1,9 @@
+<Application x:Class="MSSQL_MVVM_Sample.App"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:local="clr-namespace:MSSQL_MVVM_Sample"
+             StartupUri="MainWindow.xaml">
+    <Application.Resources>
+         
+    </Application.Resources>
+</Application>
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/App.xaml.cs b/PacticeSolution/MSSQL_MVVM_Sample/App.xaml.cs
new file mode 100644
index 0000000..9a80667
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/App.xaml.cs
@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Configuration;
+using System.Data;
+using System.Linq;
+using System.Threading.Tasks;
+using System.Windows;
+
+namespace MSSQL_MVVM_Sample
+{
+    /// <summary>
+    /// Interaction logic for App.xaml
+    /// </summary>
+    public partial class App : Application
+    {
+    }
+}
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/AssemblyInfo.cs b/PacticeSolution/MSSQL_MVVM_Sample/AssemblyInfo.cs
new file mode 100644
index 0000000..8b5504e
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/AssemblyInfo.cs
@@ -0,0 +1,10 @@
+using System.Windows;
+
+[assembly: ThemeInfo(
+    ResourceDictionaryLocation.None, //where theme specific resource dictionaries are located
+                                     //(used if a resource is not found in the page,
+                                     // or application resource dictionaries)
+    ResourceDictionaryLocation.SourceAssembly //where the generic resource dictionary is located
+                                              //(used if a resource is not found in the page,
+                                              // app, or any theme specific resource dictionaries)
+)]
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/Database/SqlManager.cs b/PacticeSolution/MSSQL_MVVM_Sample/Database/SqlManager.cs
new file mode 100644
index 0000000..6287f14
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/Database/SqlManager.cs
@@ -0,0 +1,177 @@
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Data.SqlClient;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using MSSQL_MVVM_Sample.Structure;
+
+namespace MSSQL_MVVM_Sample.Database
+{
+    public sealed class SqlManager : Singleton<SqlManager>
+    {
+        public event ExceptionEventHandler ExceptionEvent;
+
+        public SqlConnection Connection { get; set; }
+        public string ConnectionString { get; set; }
+
+        private SqlCommand _lastExecutedCommand;
+        private int _retryCount;
+
+        public bool IsRunning { get { return CheckDBConnected(); } }
+
+        public static SqlManager GetNewInstanceConnection()
+        {
+            if (Instance == null)
+                return null;
+
+            SqlManager sqlManager = new SqlManager()
+            {
+                ConnectionString = Instance.ConnectionString
+            };
+            sqlManager.GetConnection();
+            sqlManager.ExceptionEvent = Instance.ExceptionEvent;
+
+            return sqlManager;
+        }
+
+        public void SetConnectionString(string connectionString)
+        {
+            ConnectionString = connectionString;
+        }
+
+        public bool GetConnection()
+        {
+            try
+            {
+                if (Connection != null)
+                {
+                    Connection.Close();
+                    Connection.Dispose();
+                    Connection = null;
+                }
+
+                Connection = new SqlConnection(ConnectionString);
+                Connection.Open();
+
+                if (Connection.State != ConnectionState.Open)
+                    return false;
+
+                return true;
+            }
+            catch (Exception ex)
+            {
+                HandleExceptionEvent("GetConnection", ex);
+                return false;
+            }
+        }
+
+        private bool CheckDBConnected()
+        {
+            try
+            {
+                string query = "SELECT GETDATE() Date";
+                SqlCommand cmd = new SqlCommand()
+                {
+                    Connection = Connection,
+                    CommandText = query,
+                };
+
+                SqlDataReader result = cmd.ExecuteReader();
+                if (result == null || !result.HasRows)
+                    return false;
+
+                return true;
+            }
+            catch (Exception ex)
+            {
+                HandleExceptionEvent("CheckDBConnected", ex);
+                return false;
+            }
+        }
+
+        public int ExecuteNonQuery(string query)
+        {
+            try
+            {
+                lock (this)
+                {
+                    SqlCommand cmd = new SqlCommand()
+                    {
+                        Connection = Connection,
+                        CommandText = query,
+                    };
+
+                    return cmd.ExecuteNonQuery();
+                }
+            }
+            catch (Exception ex)
+            {
+                HandleExceptionEvent("ExecuteNonQuery", ex);
+                return -1;
+            }
+        }
+
+        public int ExecuteNonQuery(string query, SqlParameter[] sqlParams)
+        {
+            try
+            {
+                lock (this)
+                {
+                    SqlCommand cmd = new SqlCommand()
+                    {
+                        Connection = Connection,
+                        CommandText = query,
+                    };
+
+                    for (int i = 0; i < sqlParams.Length; i++)
+                    {
+                        cmd.Parameters.Add(sqlParams);
+                    }
+
+                    return cmd.ExecuteNonQuery();
+                }
+            }
+            catch (Exception ex)
+            {
+                HandleExceptionEvent("ExecuteNonQuery with sqlParams", ex);
+                return -1;
+            }
+        }
+
+        public DataSet ExecuteSelectQuery(string query)
+        {
+            try
+            {
+                lock (this)
+                {
+                    SqlCommand cmd = new SqlCommand()
+                    {
+                        Connection = Connection,
+                        CommandText = query,
+                    };
+                    SqlDataAdapter adt = new SqlDataAdapter()
+                    {
+                        SelectCommand = cmd,
+                    };
+
+                    DataSet ds = new DataSet();
+                    adt.Fill(ds);
+                    return ds;
+                }
+            }
+            catch (Exception ex)
+            {
+                HandleExceptionEvent("ExecuteNonQuery with sqlParams", ex);
+                return null;
+            }
+        }
+
+        private void HandleExceptionEvent(string id, Exception ex)
+        {
+            if (ExceptionEvent != null)
+                ExceptionEvent(id, ex);
+        }
+    }
+}
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/MSSQL_MVVM_Sample.csproj b/PacticeSolution/MSSQL_MVVM_Sample/MSSQL_MVVM_Sample.csproj
new file mode 100644
index 0000000..eda450c
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/MSSQL_MVVM_Sample.csproj
@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>WinExe</OutputType>
+    <TargetFramework>net6.0-windows</TargetFramework>
+    <Nullable>enable</Nullable>
+    <UseWPF>true</UseWPF>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="System.Data.SqlClient" Version="4.8.5" />
+  </ItemGroup>
+
+</Project>
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/MainWindow.xaml b/PacticeSolution/MSSQL_MVVM_Sample/MainWindow.xaml
new file mode 100644
index 0000000..676d121
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/MainWindow.xaml
@@ -0,0 +1,44 @@
+<Window x:Class="MSSQL_MVVM_Sample.MainWindow"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:local="clr-namespace:MSSQL_MVVM_Sample"
+        xmlns:vm="clr-namespace:MSSQL_MVVM_Sample.ViewModel"
+        mc:Ignorable="d"
+        Title="MainWindow" Height="300" Width="400">
+
+    <Window.DataContext>
+        <vm:MainViewModel/>
+    </Window.DataContext>
+    
+    <Grid Margin="5">
+        <Grid.RowDefinitions>
+            <RowDefinition Height="*"/>
+            <RowDefinition Height="40"/>
+        </Grid.RowDefinitions>
+
+        <DataGrid x:Name="grdMain" Grid.Row="0"
+                  AutoGenerateColumns="False"
+                  IsReadOnly="True"
+                  ItemsSource="{Binding SampleData, Mode=TwoWay}">
+            <DataGrid.Columns>
+                <DataGridTextColumn Header="Name" Width="Auto" 
+                                    Binding="{Binding Name}"/>
+                <DataGridTextColumn Header="Age" Width="Auto" 
+                                    Binding="{Binding Age}"/>
+                <DataGridTextColumn Header="Grade" Width="Auto" 
+                                    Binding="{Binding Grade}"/>
+                <DataGridTextColumn Header="Score" Width="Auto" 
+                                    Binding="{Binding Score}"/>
+            </DataGrid.Columns>
+        </DataGrid>
+
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right">
+            <Button Content="Connect" Margin="3" Width="80"
+                    Command="{Binding ConnectCommand}"/>
+            <Button Content="Search" Margin="3" Width="80"
+                    Command="{Binding SearchCommnad}"/>
+        </StackPanel>
+    </Grid>
+</Window>
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/MainWindow.xaml.cs b/PacticeSolution/MSSQL_MVVM_Sample/MainWindow.xaml.cs
new file mode 100644
index 0000000..2ab2de4
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/MainWindow.xaml.cs
@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Data;
+using System.Windows.Documents;
+using System.Windows.Input;
+using System.Windows.Media;
+using System.Windows.Media.Imaging;
+using System.Windows.Navigation;
+using System.Windows.Shapes;
+
+namespace MSSQL_MVVM_Sample
+{
+    /// <summary>
+    /// Interaction logic for MainWindow.xaml
+    /// </summary>
+    public partial class MainWindow : Window
+    {
+        public MainWindow()
+        {
+            InitializeComponent();
+        }
+    }
+}
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/Model/Student.cs b/PacticeSolution/MSSQL_MVVM_Sample/Model/Student.cs
new file mode 100644
index 0000000..8530452
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/Model/Student.cs
@@ -0,0 +1,19 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MSSQL_MVVM_Sample.Model
+{
+    internal class Student
+    {
+        public string Name { get; set; }
+
+        public int Age { get; set; }
+
+        public string Grade {get; set; }
+
+        public int Score { get; set; }
+    }
+}
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/Structure/DelegateCommand.cs b/PacticeSolution/MSSQL_MVVM_Sample/Structure/DelegateCommand.cs
new file mode 100644
index 0000000..0013968
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/Structure/DelegateCommand.cs
@@ -0,0 +1,49 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Input;
+
+namespace MSSQL_MVVM_Sample.Structure
+{
+    internal class DelegateCommand : ICommand
+    {
+        private readonly Action _execute;
+        private readonly Func<bool> _canExecute;
+
+        public event EventHandler? CanExecuteChanged;
+
+        public DelegateCommand(Action execute) : this(execute, null)
+        {
+            
+        }
+
+        public DelegateCommand(Action execute, Func<bool> canExecute)
+        {
+            _execute = execute;
+            _canExecute = canExecute;
+        }
+
+        public bool CanExecute(object? parameter)
+        {
+            if (_canExecute == null)
+                return true;
+
+            return _canExecute();
+        }
+
+        public void Execute(object? parameter)
+        {
+            _execute();
+        }
+
+        public void RaiseCanExecuteChanged()
+        {
+            if (this.CanExecuteChanged == null)
+                return;
+
+            this.CanExecuteChanged(this, EventArgs.Empty);
+        }
+    }
+}
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/Structure/Singleton.cs b/PacticeSolution/MSSQL_MVVM_Sample/Structure/Singleton.cs
new file mode 100644
index 0000000..a102f16
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/Structure/Singleton.cs
@@ -0,0 +1,17 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MSSQL_MVVM_Sample.Structure
+{
+    public class Singleton<T> where T : class, new()
+    {
+        private static readonly Lazy<T> _instnace = new Lazy<T>(() => new T());
+
+        public delegate void ExceptionEventHandler(string id, Exception ex);
+        
+        public static T Instance { get { return _instnace.Value; } }
+    }
+}
diff --git a/PacticeSolution/MSSQL_MVVM_Sample/ViewModel/MainViewModel.cs b/PacticeSolution/MSSQL_MVVM_Sample/ViewModel/MainViewModel.cs
new file mode 100644
index 0000000..f21638c
--- /dev/null
+++ b/PacticeSolution/MSSQL_MVVM_Sample/ViewModel/MainViewModel.cs
@@ -0,0 +1,140 @@
+using MSSQL_MVVM_Sample.Database;
+using MSSQL_MVVM_Sample.Model;
+using MSSQL_MVVM_Sample.Structure;
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.ComponentModel;
+using System.Data;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Input;
+using System.Windows.Interop;
+
+namespace MSSQL_MVVM_Sample.ViewModel
+{
+    internal class MainViewModel : INotifyPropertyChanged
+    {
+        private Student _student;
+
+        public event PropertyChangedEventHandler? PropertyChanged;
+
+        public MainViewModel()
+        {
+            _student = new Student();
+            SqlManager.Instance.ConnectionString = "Data Source=peacecloud.synology.me,21433;Initial Catalog=Study;User ID=study;Password=Study1234";
+        }
+
+        public string Name
+        {
+            get { return _student.Name; }
+            set
+            {
+                _student.Name = value;
+                OnPropertyChanged(nameof(this.Name));
+            }
+        }
+
+        public int Age
+        {
+            get { return _student.Age; }
+            set
+            {
+                _student.Age = value;
+                OnPropertyChanged(nameof(this.Age));
+            }
+        }
+
+        public string Grade
+        {
+            get { return _student.Grade; }
+            set
+            {
+                _student.Grade = value;
+                OnPropertyChanged(nameof(this.Grade));
+            }
+        }
+
+        public int Score
+        {
+            get { return _student.Score; }
+            set
+            {
+                _student.Score = value;
+                OnPropertyChanged(nameof(this.Score));
+            }
+        }
+
+        private ObservableCollection<Student> _sampleData;
+        public ObservableCollection<Student> SampleData
+        {
+            get
+            {
+                if (_sampleData == null)
+                    _sampleData = new ObservableCollection<Student>();
+
+                return _sampleData;
+            }
+            set { _sampleData = value; }
+        }
+
+        private ICommand _connectCommand;
+        public ICommand ConnectCommand
+        {
+            get { return _connectCommand ?? (_connectCommand = new DelegateCommand(ConnectDatabase)); }
+        }
+
+        private ICommand _searchCommand;
+        public ICommand SearchCommnad
+        {
+            get { return _searchCommand ?? (_searchCommand = new DelegateCommand(SearchData)); }
+        }
+
+        private void ConnectDatabase()
+        {
+            if (!SqlManager.Instance.GetConnection())
+            {
+                MessageBox.Show("Fail to connect to database", "Error");
+                return;
+            }
+
+            MessageBox.Show("Success to connect to database", "Inform");
+        }
+
+        private void SearchData()
+        {
+            if (this.SampleData != null)
+                this.SampleData.Clear();
+
+            string query = @"SELECT * FROM Student";
+
+            DataSet ds = SqlManager.Instance.ExecuteSelectQuery(query);
+            if (ds == null || ds.Tables.Count < 1 || ds.Tables[0].Rows == null || ds.Tables[0].Rows.Count < 1)
+            {
+                MessageBox.Show("No data in table", "Alert");
+                return;
+            }
+
+            foreach (DataRow row in ds.Tables[0].Rows)
+            {
+                Student student = new Student()
+                {
+                    Name = row["Name"].ToString(),
+                    Age = (int)row["Age"],
+                    Grade = row["Grade"].ToString(),
+                    Score = (int)row["Score"]
+                };
+
+                this.SampleData.Add(student);
+            }
+        }
+
+        private void OnPropertyChanged([CallerMemberName] string propertyName = null)
+        {
+            this.PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+    }
+}
diff --git a/PacticeSolution/PacticeSolution.sln b/PacticeSolution/PacticeSolution.sln
index f3584b8..52af3b2 100644
--- a/PacticeSolution/PacticeSolution.sln
+++ b/PacticeSolution/PacticeSolution.sln
@@ -89,7 +89,9 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DashedFigure", "DashedFigur
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AddressBook_MVVMSample", "AddressBook_MVVMSample\AddressBook_MVVMSample.csproj", "{6A452509-3DEB-41A3-8AA3-8DB4BE948D28}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AddressBook_MVVMSampleV2", "AddressBook_MVVMSampleV2\AddressBook_MVVMSampleV2.csproj", "{0CE2A390-5A8B-4F13-9F60-A4AF77F0B1F3}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "AddressBook_MVVMSampleV2", "AddressBook_MVVMSampleV2\AddressBook_MVVMSampleV2.csproj", "{0CE2A390-5A8B-4F13-9F60-A4AF77F0B1F3}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MSSQL_MVVM_Sample", "MSSQL_MVVM_Sample\MSSQL_MVVM_Sample.csproj", "{BAAF8254-74D1-406D-9765-43DCA9F939C7}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -273,6 +275,10 @@ Global
 		{0CE2A390-5A8B-4F13-9F60-A4AF77F0B1F3}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{0CE2A390-5A8B-4F13-9F60-A4AF77F0B1F3}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{0CE2A390-5A8B-4F13-9F60-A4AF77F0B1F3}.Release|Any CPU.Build.0 = Release|Any CPU
+		{BAAF8254-74D1-406D-9765-43DCA9F939C7}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{BAAF8254-74D1-406D-9765-43DCA9F939C7}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{BAAF8254-74D1-406D-9765-43DCA9F939C7}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{BAAF8254-74D1-406D-9765-43DCA9F939C7}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE