SQLiteOpenHelper自动建立数据库

private static class DatabaseHelper extends SQLiteOpenHelper{
private static final String DATABASE_CREATE="create table mytable"+
"(id integer  primary key autoincrement,"+
"name text not null,"+
"address text not null,"+
"createtime text not null);";
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
}

@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL(DATABASE_CREATE);

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS mytable");
onCreate(db);

}
}

外部调用SQLiteOpenHelper.getWritableDatabase()方法时,如果没有可打开的数据库,

程序将自动调用重写的SQLiteOpenHelper.onCreate(SQLiteDatabase db)方法,来新建

一个数据库