insert id returns always -1 and data is not inserted in database. please somebody help me

when i insert the data then insert id always returns -1 this is my data base table.my database is created successfully. So, please tell me what i do to solve this problem.

query3 = "CREATE TABLE IF NOT EXISTS `" + StaticData.SUBJECT_TABLE_NAME + "` ("
                + "`subject_id` int(11) NOT NULL,"
                + "`subject_name` varchar(100) DEFAULT NULL,"
                + " PRIMARY KEY (`subject_id`)"
                + ");";

public long insertSubject(TeacherModel queryValues) {
            long insertId = -1;
            ContentValues values = new ContentValues();

            values.put("id", queryValues.getSubject_id());
            values.put("name", queryValues.getSubject());

            if(database != null) {

                 insertId = database.insert(StaticData.SUBJECT_TABLE_NAME, null,
                        values);
            }
            Log.w(DataInteract.class.getName(),
                    "Subject::" + values + "insertID=" + insertId);

            return insertId;
        }