update

Updates an object (or multiple objects) and saves it to the database, if validations pass. The resulting object is returned whether the object was saved successfully to the database or not.

Parameters

• id - This should be the id or an array of ids to be updated. Optional argument, defaults to all records in the relation.

• attributes - This should be a hash of attributes or an array of hashes.

Examples

# Updates one record
Person.update(15, user_name: "Samuel", group: "expert")

# Updates multiple records
people = { 1 => { "first_name" => "David" }, 2 => { "first_name" => "Jeremy" } }
Person.update(people.keys, people.values)

# Updates multiple records from the result of a relation
people = Person.where(group: "expert")
people.update(group: "masters")

Note: Updating a large number of records will run an UPDATE query for each record, which may cause a performance issue. When running callbacks is not needed for each record update, it is preferred to use {update_all}[rdoc-ref:Relation#update_all] for updating all records in a single query.