目的读取sqlite3的数据。
数据

//select * from book;
1|Dan Brown|10.99|454|The Da vinvi Code

    SQLiteDatabase db = dbHelper.getWritableDatabase();
    Cursor cursor = db.query("book",null,null,null,null,null,null);
    if(cursor.moveToFirst()){
        do{
            String name = cursor.getString(cursor.getColumnIndex("name"));
            String author = cursor.getString(cursor.getColumnIndex("author"));
            int pages = cursor.getInt(cursor.getColumnIndex("page"));
            double price = cursor.getDouble(cursor.getColumnIndex("price"))
                Log.d("MainActivity","book name is" +name);
                Log.d("MainActivity","book author is"+author);
                Log.d("MainActivity","book pages is"+pages);
                Log.d("MainActivity","book price is"+price);
            }while (cursor.moveToNext());
            }

我自己调试发现是int pages = cursor.getInt(cursor.getColumnIndex("page"));发生了错误，错误显示信息

java.lang.IllegalStateException: Couldn't read row 0, col -1 from CursorWindow.  Make sure the Cursor is initialized correctly before accessing data from it.

建表

    create table book
    (
                id integer primary key autoincrement,
                author text,
                price real,
                pages integer,
                name text.
    )

我没有学过数据库除了语法可能出错其他不会有问题。