Collection.first() - zuki/Dexie.js GitHub Wiki
collection.first(callback)
| callback: Function | function (item) { } | optional |
| item: Object | First item in the collection if any. Otherwise undefined |
If callback is omitted and operation succeeds, returned Promise will resolve with the result of the operation, calling any Promise.then() callback.
If callback is specified and operation succeeds, given callback will be called and the returned Promise will resolve with the return value of given callback.
If operation fails, returned promise will reject, calling any Promise.catch() callback.