ActiveRecord query alias field name output

Question

Let's say I have a table World.

I have a field called foo within the table. I want to query the World table and select foo, but I would like to alias it as bar in the subsequent conversion to JSON output.

Is there any way to alias the field name for just this one ActiveRecord query? Not looking to alias the field through the entire application.

Answer 1

Just use the SQL alias feature in a select method call:

w = World.select("foo as bar").first
w.bar # returns value for foo
w.foo # ActiveModel::MissingAttributeError

Answer 2

I avoid writing SQL as much as I can, so I would rather use ARel to build the query. Something like

World.select(World.arel_table['foo'].as('bar'))

Using some syntactic sugar, it's just:

at = World.arel_table
World.select(at['foo'].as('bar'))