nallwhy
Append fields using select query on Ecto
I have a schema and it has many fields and one belongs_to association.
I want to query this model with one field of associated model like below.
def MyModel do
schema "my_models" do
field(:field0, :string)
field(:field1, :string)
field(:field2, :string)
field(:field3, :string)
field(:field4, :string)
field(:field5, :string)
field(:field6, :string)
field(:field7, :string)
field(:field8, :string)
field(:other_model_id)
end
end
def list() do
MyModel
|> join(:inner, [m], o in OtherModel, m.other_model_id == o.id)
|> select([m, o], %{field0: m.field0, field1: m.field1, ... other_model_value: o.value})
end
But I don’t want to repeat field0, field1, …
Is there a better way to do this?
Thanks!
Marked As Solved
nallwhy
I found a way to do it.
def MyModel do
schema "my_models" do
field(:field0, :string)
...
field(:field8, :string)
field(:other_model_id, :integer)
# Add a virtual field
field(:other_model_value, :integer, virtual: true)
end
end
def list() do
MyModel
|> join(:inner, [m], o in OtherModel, m.other_model_id == o.id)
|> select([m, o], %{m | other_model_value: o.value})
end
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