Unity, loading image from Sqlite - image

Question

hi guys this is my first time using Sqlite, i managed to retrieve the text and display it, however the image shows a red question mark even tho i followed this : unity sqlite tutorial
here is my code :
private void readQuestionsFromDB(){
string conn = "URI=file:" + Application.dataPath + "/quizdb.s3db"; //Path to database.
IDbConnection dbconn;
dbconn = (IDbConnection) new SqliteConnection(conn);
dbconn.Open(); //Open connection to the database.
IDbCommand dbcmd = dbconn.CreateCommand();
string sqlQuery = "SELECT id, statement, answer, image " + "FROM questions";
dbcmd.CommandText = sqlQuery;
IDataReader reader = dbcmd.ExecuteReader();
while (reader.Read())
{
string statement = reader.GetString(1);
answerint = reader.GetInt32(2);
byte[] img = (byte[])reader["image"];
Question q = new Question(statement, answer, img);
questions.Add(q);
}
reader.Close();
reader = null;
dbcmd.Dispose();
dbcmd = null;
dbconn.Close();
dbconn = null;
}
Then i try to display the image from the start method :
readQuestionsFromDB();
statement.text = questions[0].statement;
Texture2D tex = new Texture2D(800,400); //image is 800/400
tex.LoadImage(questions[0].image);
image.GetComponent<Image>().sprite = Sprite.Create(tex, new Rect(0,0,tex.width,tex.height),new Vector2(0.5f, 0.5f));
Here is the outcome :
image
Thank you in advance for your help!