ColumnAttribute.DbType Property   
Definition
Important
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Gets or sets the type of the database column.
public:
 property System::String ^ DbType { System::String ^ get(); void set(System::String ^ value); };
	public string DbType { get; set; }
	member this.DbType : string with get, set
	Public Property DbType As String
	Property Value
String value that specifies the exact text that defines the column in a Transact-SQL table declaration.
Examples
[Column(Storage="_FirstName", DbType="NVarChar(10) NOT NULL", CanBeNull=false)]
public string FirstName
{
    get
    {
        return this._FirstName;
    }
    set
    {
        if ((this._FirstName != value))
        {
            this.OnFirstNameChanging(value);
            this.SendPropertyChanging();
            this._FirstName = value;
            this.SendPropertyChanged("FirstName");
            this.OnFirstNameChanged();
        }
    }
}
<Column(Storage:="_FirstName", DbType:="NVarChar(10) NOT NULL", CanBeNull:=false)>  _
Public Property FirstName() As String
    Get
        Return Me._FirstName
    End Get
    Set
        If ((Me._FirstName = value)  _
                    = false) Then
            Me.OnFirstNameChanging(value)
            Me.SendPropertyChanging
            Me._FirstName = value
            Me.SendPropertyChanged("FirstName")
            Me.OnFirstNameChanged
        End If
    End Set
End Property
	Remarks
Use this property to specify the exact text that defines the column in a Transact-SQL table declaration. Specify the DbType property only if you plan to use CreateDatabase to create an instance of the database.
The default value of DbType is inferred from the member type. For more information, see SQL-CLR Type Mapping.