CREATE PROCEDURE dbo.AuthenticateLogin(
    @Username VARCHAR(100),
    @Password VARCHAR(100),
    @response NVARCHAR(500) OUTPUT
)AS
BEGIN
    DECLARE @UserID INT
    IF(EXISTS(SELECT username FROM users WHERE username = @Username))
    BEGIN
        SET @UserID = (SELECT users_id FROM users WHERE username = @Username AND user_password = @Password)
        IF @UserID IS NULL
            SET @response = 'Incorrect Password'
        ELSE
            Set @response = 'Success'
    END
    ELSE
        SET @response = 'Invalid Login'
END
GO

Public Function AuthenticateLogin(ByVal username As String, ByVal password As String) As Boolean
    Dim CMD As New SqlCommand("AuthenticateLogin")
    CMD.Parameters.Add("@UserName", SqlDbType.VarChar).Value = username
    CMD.Parameters.Add("@Password", SqlDbType.VarChar).Value = password
    AuthenticateLogin = ExecuteCMDWithReturnValue(CMD)
End Function

Public Function ExecuteCMDWithReturnValue(ByRef CMD As SqlCommand) As Boolean
    Try
        OpenDBConnection()
        CMD.Parameters.Add("@response", SqlDbType.NVarChar).Direction = ParameterDirection.ReturnValue
        CMD.Connection = DB_CONNECTION
        CMD.CommandType = CommandType.StoredProcedure
        CMD.ExecuteNonQuery()
        Dim result As Object = CMD.Parameters("@response").Value
        Return If(Convert.ToInt32(result) = 1, False, True)
    Catch ex As Exception
        Throw New Exception("Database Error: " & ex.Message)
        Return False
    Finally
        CloseDBConnection()
    End Try
End Function