Updating Objects in Collections #

When updating an object in a Collection, you can use special modifier commands to more granularly change property values.

$inc #

The $inc command increments the value of a given Number property.

// Give a player 5 points
  score: {$inc: 5}

$push #

The $push command adds a value to an Array property.

// Add a follower to a user by storing their id.
  followers: {$push: 'a59551a90be9abd8'}

$pushAll #

The $pushAll command adds multiple values to an Array property.

// Add mentions of users
  mentions: {
    $pushAll: ['a59551a90be9abd8', 'd0be45d1445d3809']

$pull #

The $pull command removes a value from an Array property.

// Remove a user from followers
  followers: {$pull: 'a59551a90be9abd8'}

Note: If there is more than one matching value in the Array, this will remove all of them

$pullAll #

The $pullAll command removes multiple values from an Array property.

// Remove multiple users
  followers: {$pullAll: ['a59551a90be9abd8', 'd0be45d1445d3809']}

Note: This will remove all of the matching values from the Array