学步园

var db = indexedDB.open('books', 'Book store', false);
if (db.version !== '1.0') {
  var olddb = indexedDB.open('books', 'Book store');
  olddb.createObjectStore('books', 'isbn');
  olddb.createIndex('BookAuthor', 'books', 'author', false);
  olddb.setVersion("1.0");  
}
// db.version === "1.0";  
var index = db.openIndex('BookAuthor');
var matching = index.get('fred');
if (matching)
  report(matching.isbn, matching.name, matching.author);
else
  report(null);