android - Duplicate rows in sqlite database -

i have android app local sqlite database have problem duplicate row. every time when start app, addding items db item same id exist there. problem cannot update/rewrite rows has same id. db: link

declarations:

// database name private static final string database_name = "foodsdb";  // contacts table name private static final string table_foods = "tablefoods";  // contacts table columns names private static final string key_id = "id"; private static final string key_foodname = "food_name"; private static final string key_alergen_no = "alergen_numbers"; private static final string key_date = "date"; private static final string key_food_number = "food_number"; 

db create table:

  // creating table @override public void oncreate(sqlitedatabase db) {     string create_foods_table = "create table " + table_foods + "("             + key_id + " text,"  + key_foodname + " text,"             + key_alergen_no + " text," + key_date + " text," + key_food_number + " integer"+")";     db.execsql(create_foods_table); } 

db insert:

 // adding new food void addfood(foodsdb food) {     sqlitedatabase db = this.getwritabledatabase();      contentvalues values = new contentvalues();     values.put(key_id, food.getid());     values.put(key_foodname, food.getfoodname());     values.put(key_alergen_no, food.getalergenynumbers());     values.put(key_date,food.getdate());     values.put(key_food_number,food.getfoodnumber());      db.begintransaction();     try {         long rowid = db.insertorthrow(table_foods, null, values);         if (rowid == -1) {             // insertion failed             string whereclause = key_date;             //string[] whereargs = new string[] {values.getasstring(key_date)};             db.update(table_foods, values, whereclause, null);         }         db.settransactionsuccessful();     } {         db.endtransaction();     }     db.close(); // closing database connection } 

any idea why have more rows same id in db? try set id primary key not work.