Ecto.Changeset.merge
You're seeing just the function
merge
, go back to Ecto.Changeset module for more information.
Specs
Merges two changesets.
This function merges two changesets provided they have been applied to the
same data (their :data
field is equal); if the data differs, an
ArgumentError
exception is raised. If one of the changesets has a :repo
field which is not nil
, then the value of that field is used as the :repo
field of the resulting changeset; if both changesets have a non-nil
and
different :repo
field, an ArgumentError
exception is raised.
The other fields are merged with the following criteria:
params
- params are merged (not deep-merged) giving precedence to the params ofchangeset2
in case of a conflict. If both changesets have their:params
fields set tonil
, the resulting changeset will have its params set tonil
too.changes
- changes are merged giving precedence to thechangeset2
changes.errors
andvalidations
- they are simply concatenated.required
- required fields are merged; all the fields that appear in the required list of both changesets are moved to the required list of the resulting changeset.
Examples
iex> changeset1 = cast(%Post{}, %{title: "Title"}, [:title])
iex> changeset2 = cast(%Post{}, %{title: "New title", body: "Body"}, [:title, :body])
iex> changeset = merge(changeset1, changeset2)
iex> changeset.changes
%{body: "Body", title: "New title"}
iex> changeset1 = cast(%Post{body: "Body"}, %{title: "Title"}, [:title])
iex> changeset2 = cast(%Post{}, %{title: "New title"}, [:title])
iex> merge(changeset1, changeset2)
** (ArgumentError) different :data when merging changesets