diff --git a/PacticeSolution/MVVMDatabaseSample/App.xaml b/PacticeSolution/MVVMDatabaseSample/App.xaml
new file mode 100644
index 0000000..70fcec1
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/App.xaml
@@ -0,0 +1,9 @@
+<Application x:Class="MVVMDatabaseSample.App"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:local="clr-namespace:MVVMDatabaseSample"
+             StartupUri="MainWindow.xaml">
+    <Application.Resources>
+         
+    </Application.Resources>
+</Application>
diff --git a/PacticeSolution/MVVMDatabaseSample/App.xaml.cs b/PacticeSolution/MVVMDatabaseSample/App.xaml.cs
new file mode 100644
index 0000000..1586b49
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/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 MVVMDatabaseSample
+{
+    /// <summary>
+    /// Interaction logic for App.xaml
+    /// </summary>
+    public partial class App : Application
+    {
+    }
+}
diff --git a/PacticeSolution/MVVMDatabaseSample/AssemblyInfo.cs b/PacticeSolution/MVVMDatabaseSample/AssemblyInfo.cs
new file mode 100644
index 0000000..8b5504e
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/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/MVVMDatabaseSample/MVVMDatabaseSample.csproj b/PacticeSolution/MVVMDatabaseSample/MVVMDatabaseSample.csproj
new file mode 100644
index 0000000..3a4a13a
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/MVVMDatabaseSample.csproj
@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>WinExe</OutputType>
+    <TargetFramework>net6.0-windows</TargetFramework>
+    <Nullable>enable</Nullable>
+    <UseWPF>true</UseWPF>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Folder Include="View\" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="System.Data.SqlClient" Version="4.8.5" />
+  </ItemGroup>
+
+</Project>
diff --git a/PacticeSolution/MVVMDatabaseSample/MainWindow.xaml b/PacticeSolution/MVVMDatabaseSample/MainWindow.xaml
new file mode 100644
index 0000000..58c1f57
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/MainWindow.xaml
@@ -0,0 +1,40 @@
+<Window x:Class="MVVMDatabaseSample.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:MVVMDatabaseSample" xmlns:viewmodel="clr-namespace:MVVMDatabaseSample.ViewModel"
+        mc:Ignorable="d"
+        Title="MainWindow" Height="350" Width="500">
+
+    <Window.DataContext>
+        <viewmodel:ViewModelMain/>
+    </Window.DataContext>
+    
+    <Grid>
+        <Grid.ColumnDefinitions>
+            <ColumnDefinition Width="*"/>
+            <ColumnDefinition Width="150"/>
+            <ColumnDefinition Width="200"/>
+        </Grid.ColumnDefinitions>
+        <Grid.RowDefinitions>
+            <RowDefinition Height="*"/>
+            <RowDefinition Height="70"/>
+        </Grid.RowDefinitions>
+
+        <DataGrid x:Name="grdMain" Grid.ColumnSpan="3" Margin="5"
+                  AutoGenerateColumns="False"
+                  ItemsSource="{Binding SampleData, Mode=TwoWay, NotifyOnSourceUpdated=True, NotifyOnTargetUpdated=True}">
+            <DataGrid.Columns>
+                <DataGridTextColumn MinWidth="10" Width="Auto" Header="Name" Binding="{Binding Name}"/>
+                <DataGridTextColumn MinWidth="100" Width="Auto" Header="AGE" Binding="{Binding Age}"/>
+                <DataGridTextColumn MinWidth="100" Width="Auto" Header="GRADE" Binding="{Binding Grade}"/>
+                <DataGridTextColumn MinWidth="200" Width="*" Header="SCORE" Binding="{Binding Score}"/>
+            </DataGrid.Columns>
+        </DataGrid>
+
+        <Button Grid.Column="0" Grid.Row="1" Margin="5" Content="Connect" Command="{Binding ConnectCommand}"/>
+        <Button Grid.Column="1" Grid.Row="1" Margin="5" Content="Search" Command="{Binding SelectCommand}"/>
+        <Button Grid.Column="2" Grid.Row="1" Margin="5" Content="Update" IsEnabled="False" Command="{Binding Update}"/>
+    </Grid>
+</Window>
diff --git a/PacticeSolution/MVVMDatabaseSample/MainWindow.xaml.cs b/PacticeSolution/MVVMDatabaseSample/MainWindow.xaml.cs
new file mode 100644
index 0000000..839f250
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/MainWindow.xaml.cs
@@ -0,0 +1,35 @@
+using MVVMDatabaseSample.Util;
+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 MVVMDatabaseSample
+{
+    /// <summary>
+    /// Interaction logic for MainWindow.xaml
+    /// </summary>
+    public partial class MainWindow : Window
+    {
+        public MainWindow()
+        {
+            InitializeComponent();
+            InitInstance();
+        }
+
+        private void InitInstance()
+        {
+            SqlDBManager.Instance.ConnectionString = "Data Source=peacecloud.synology.me,21433;Initial Catalog=Study;User ID=study;Password=Study1234";
+        }
+    }
+}
diff --git a/PacticeSolution/MVVMDatabaseSample/Model/Student.cs b/PacticeSolution/MVVMDatabaseSample/Model/Student.cs
new file mode 100644
index 0000000..d01a5f9
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/Model/Student.cs
@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MVVMDatabaseSample.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/MVVMDatabaseSample/Util/SqlDBManager.cs b/PacticeSolution/MVVMDatabaseSample/Util/SqlDBManager.cs
new file mode 100644
index 0000000..e2c0e57
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/Util/SqlDBManager.cs
@@ -0,0 +1,54 @@
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Data.SqlClient;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MVVMDatabaseSample.Util
+{
+    internal sealed class SqlDBManager
+    {
+        public static SqlDBManager Instance { get; private set; } = new SqlDBManager();
+
+        public string ConnectionString { get; set; }
+
+        public SqlConnection Connection { get; private set; }
+
+        private SqlCommand _sqlCommand;
+
+        public bool GetConnection()
+        {
+            try
+            {
+                _sqlCommand = new SqlCommand();
+                _sqlCommand.Connection = this.Connection;
+
+                this.Connection = new SqlConnection(ConnectionString);
+                this.Connection.Open();
+
+                return true;
+            }
+            catch (Exception)
+            {
+                return false;
+            }
+        }
+
+        public DataSet ExecuteQuery(DataSet ds, string query)
+        {
+            ds.Reset();
+            lock (this)
+            {
+                SqlDataAdapter adapter = new SqlDataAdapter();
+                adapter.SelectCommand = _sqlCommand;
+                adapter.SelectCommand.Connection = this.Connection;
+                adapter.SelectCommand.CommandText = query;
+                adapter.Fill(ds);
+            }
+
+            return ds;
+        }
+    }
+}
diff --git a/PacticeSolution/MVVMDatabaseSample/ViewModel/DelegateCommand.cs b/PacticeSolution/MVVMDatabaseSample/ViewModel/DelegateCommand.cs
new file mode 100644
index 0000000..0b884df
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/ViewModel/DelegateCommand.cs
@@ -0,0 +1,47 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Input;
+
+namespace MVVMDatabaseSample.ViewModel
+{
+    internal class DelegateCommand : ICommand
+    {
+        private readonly Func<bool> _canExecute;
+        private readonly Action _execute;
+
+        public event EventHandler? CanExecuteChanged;
+
+        public DelegateCommand(Action execute, Func<bool> canExecute)
+        {
+            _execute = execute;
+            _canExecute = canExecute;
+        }
+
+        public DelegateCommand(Action execute) : this(execute, null)
+        {
+            
+        }        
+
+        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)
+                this.CanExecuteChanged(this, EventArgs.Empty);
+        }
+    }
+}
diff --git a/PacticeSolution/MVVMDatabaseSample/ViewModel/ViewModelMain.cs b/PacticeSolution/MVVMDatabaseSample/ViewModel/ViewModelMain.cs
new file mode 100644
index 0000000..4b5aafd
--- /dev/null
+++ b/PacticeSolution/MVVMDatabaseSample/ViewModel/ViewModelMain.cs
@@ -0,0 +1,160 @@
+using MVVMDatabaseSample.Model;
+using MVVMDatabaseSample.Util;
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.ComponentModel;
+using System.Data;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Controls.Primitives;
+using System.Windows.Input;
+
+namespace MVVMDatabaseSample.ViewModel
+{
+    internal class ViewModelMain : INotifyPropertyChanged
+    {
+        private Student _student = new Student();
+        private ObservableCollection<Student> _sampleData;
+        private ICommand _connectCommand;
+        private ICommand _selectCommand;
+        private ICommand _loadedCommand;
+
+        public event PropertyChangedEventHandler? PropertyChanged;
+
+        public string Name
+        {
+            get { return _student.Name; }
+            set
+            {
+                _student.Name = value;
+                OnPropertyChanged("Name");
+            }
+        }
+
+        public int Age
+        {
+            get { return _student.Age; }
+            set
+            {
+                _student.Age = value;
+                OnPropertyChanged("Age");
+            }
+        }
+
+        public string Grage
+        {
+            get { return _student.Grade; }
+            set
+            {
+                _student.Grade = value;
+                OnPropertyChanged("Grade");
+            }
+        }
+
+        public int Score
+        {
+            get { return _student.Score; }
+            set
+            {
+                _student.Score = value;
+                OnPropertyChanged("Score");
+            }
+        }
+
+        public ObservableCollection<Student> SampleData
+        {
+            get
+            {
+                if (_sampleData == null)
+                    _sampleData = new ObservableCollection<Student>();
+
+                return _sampleData;
+            }
+            set { _sampleData = value; }
+        }
+
+        public ICommand ConnectCommand
+        {
+            get
+            {
+                if (_connectCommand == null)
+                    _connectCommand = new DelegateCommand(Connect);
+
+                return _connectCommand;
+            }
+        }
+
+        public ICommand SelectCommand
+        {
+            get
+            {
+                if (_selectCommand == null)
+                    _selectCommand = new DelegateCommand(Select);
+
+                return _selectCommand;
+            }
+        }
+
+        public ICommand LoadedCommand
+        {
+            get
+            {
+                if (_loadedCommand == null)
+                    _loadedCommand = new DelegateCommand(Load);
+
+                return _loadedCommand;
+            }
+        }
+
+        private void Connect()
+        {
+            string message;
+            if (!SqlDBManager.Instance.GetConnection())
+                message = "Fail to connect";
+            else
+                message = "Success to connect";
+
+            MessageBox.Show(message);
+        }
+
+        private void Select()
+        {
+            DataSet ds = new DataSet();
+            string qry = "SELECT * FROM Student";
+            SqlDBManager.Instance.ExecuteQuery(ds, qry);
+            if (ds.Tables.Count < 1)
+                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"],
+                };
+                _sampleData.Add(student);
+            }
+        }
+
+        private void Load()
+        {
+            string message;
+            if (!SqlDBManager.Instance.GetConnection())
+                message = "Fail to connect";
+            else
+                message = "Success to connect";
+
+            MessageBox.Show(message);
+        }
+
+        protected void OnPropertyChanged(string propertyName)
+        {
+            this.PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+    }
+}
diff --git a/PacticeSolution/PacticeSolution.sln b/PacticeSolution/PacticeSolution.sln
index 2e29af9..bf40cb8 100644
--- a/PacticeSolution/PacticeSolution.sln
+++ b/PacticeSolution/PacticeSolution.sln
@@ -15,6 +15,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MVVMSample", "MVVMSample\MV
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ResourceSample", "ResourceSample\ResourceSample.csproj", "{858EC308-9ABD-44C1-92E1-59911F60FEB9}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MVVMDatabaseSample", "MVVMDatabaseSample\MVVMDatabaseSample.csproj", "{B0A8E6DE-C6A2-488E-A148-9E7812F615F2}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -45,6 +47,10 @@ Global
 		{858EC308-9ABD-44C1-92E1-59911F60FEB9}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{858EC308-9ABD-44C1-92E1-59911F60FEB9}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{858EC308-9ABD-44C1-92E1-59911F60FEB9}.Release|Any CPU.Build.0 = Release|Any CPU
+		{B0A8E6DE-C6A2-488E-A148-9E7812F615F2}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{B0A8E6DE-C6A2-488E-A148-9E7812F615F2}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{B0A8E6DE-C6A2-488E-A148-9E7812F615F2}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{B0A8E6DE-C6A2-488E-A148-9E7812F615F2}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/PacticeSolution/ResourceSample/MainWindow.xaml.cs b/PacticeSolution/ResourceSample/MainWindow.xaml.cs
index 0651521..25e50f5 100644
--- a/PacticeSolution/ResourceSample/MainWindow.xaml.cs
+++ b/PacticeSolution/ResourceSample/MainWindow.xaml.cs
@@ -31,7 +31,7 @@ namespace ResourceSample
             if (_clickCount % 2 == 0)
                 this.Resources["CustomEventColor"] = new SolidColorBrush((Color)ColorConverter.ConvertFromString("#3de385"));
             else
-                this.Resources["CustomEventColor"] = Resources["CustomRed"];
+                this.Resources["CustomEventColor"] = Application.Current.FindResource("CustomRed");
 
             _clickCount++;
         }