Queries

When listening to paths, it is possible to modify the query with any of Firebase's included query methods. Below are examples using Firebase query methods as well as other methods that are included (such as 'populate').

orderByChild

To order the query by a child within each object, user orderByChild.

Example

Ordering a list of todos by the text parameter of the todo item (placing them in alphabetical order).

@firebase(['/todos#orderByChild=text'])

orderByKey

Order a list by the key of each item. Since push keys contain time, this is also a way of ordering by when items were created.

Example

Ordering a list of todos based on their key (puts them in order of when they were created)

@firebase(['/todos#orderByKey'])

orderByValue

Runs Firebase's orderByValue

Order a list by the value of each object

Example

Ordering a list of score's based on score's value

@firebase([`scores#orderByValue`])

orderByPriority

Runs Firebase's orderByPriority

Example

Ordering a list based on priorities

@firebase([`scores#orderByPriority`])

limitToFirst

Limit query results to the first n number of results

Examples

1. Displaying only the first todo item

   @firebase(['/todos#limitToFirst'])
   

2. Displaying only the first 10 todo items

   @firebase(['/todos#limitToFirst=10'])
   

limitToLast

Limit query results to the last n number of results

Examples

1. Only the last todo item

   @firebase(['/todos#limitToFirst'])
   

2. Only the last 10 todo items

   @firebase(['/todos#limitToFirst=10'])
   

   startAt

Limit query results to include a range starting at a specific number

Example

1. Starting at the fifth item

   @firebase([
    'todos#startAt=5&limitToFirst=2'
   ])
   

2. Paginate results

   @firebase([
    'todos#startAt=5&limitToFirst=10'
   ])
   

   endAt

   @firebase([
   'todos#orderByChild=added&startAt=1&endAt=5'
   ])
   

equalTo

@firebase([
  'todos#orderByChild=added&startAt=5&limitToFirst=2'
])

Once

To load a firebase location once instead of binding, the once option can be used:

@firebase([
  { type: 'once', path: '/todos' }
])

Populate

Populate allows you to replace IDs within your data with other data from Firebase. This is very useful when trying to keep your data flat. Some would call it a join, but it was modeled after the mongo populate method.

Visit Populate Section for full documentation.