To search an IndexedDB database by key range or value, we must implement the
IDBKeyrange object and call on the lowerbound and upperbound methods.
lowerBound() generates a new key range with only a lower bound. It is closed by default and includes the lower endpoint value. The
upperBound() function generates a new upper-bound key range, and it is closed by default and includes the upper endpoint value. The following methods include store get,
getAll, getKey, getAllKeys, or count to perform the actual search. They accept a query argument that can be either an exact key or a key range.
Code Example :
// get one book
books.get('js');
// get books with 'css' <= id <= 'html'
books.getAll(IDBKeyRange.bound('css', 'html'));
// get books with id < 'html'
books.getAll(IDBKeyRange.upperBound('html', true));
// get all books
books.getAll();
// get all keys, where id > 'js'
books.getAllKeys(IDBKeyRange.lowerBound('js', true));?
