android - Getting error on inserting data on table using SQLite -

i'm building android mobile app , use sqlite database. i'm having trouble inserting record on table , returns toast message "insert failed" meaning saving data unsuccessful.

public class databasehelper extends sqliteopenhelper {      public static final string database_name = "mobilebuddy.db";     public static final string table_name = "bets_table";     public static final string col_1 = "combination";     public static final string col_2 = "draw_date";     public static final string col_3 = "trans_date";      public databasehelper(context context) {         super(context, database_name, null, 1);     }      @override     public void oncreate(sqlitedatabase db) {         db.execsql("create table " + table_name + "(" + col_1 + " text, " + col_2 + " datetime, " + col_3 + " datetime)");     }      @override     public void onupgrade(sqlitedatabase db, int oldversion, int newversion) {         db.execsql("drop table if exists " + table_name);         oncreate(db);     }      public boolean insertbetdata(string combination, string drawdate, string transdate) {         sqlitedatabase db = this.getwritabledatabase();         contentvalues contentvalues = new contentvalues();         contentvalues.put(col_1, combination);         contentvalues.put(col_2, drawdate);         contentvalues.put(col_3, transdate);         long result = db.insert(table_name, null, contentvalues);         if (result == 1) return true; else return false;     } } 

i used code below in onclick event , should trigger insertion of data on table.

calendar = calendar.getinstance(); simpledateformat sdf = new simpledateformat("yyyy-mm-dd"); boolean issave = lottodb.insertbetdata(validbet, sdf.format(calendar.gettime()), sdf.format(calendar.gettime())); if (issave == true)     toast.maketext(playsixnumbers.this, "inserted", toast.length_short).show(); else     toast.maketext(playsixnumbers.this, "insert failed", toast.length_short).show(); 

what's wrong codes? hope understand inquiry..

the documentation says insert() function returns

the row id of newly inserted row, or -1 if error occurred

the id not 1. have check return value not error value.

and better idea use insertorthrow() instead useful error message.