There is a matter of choice standards within the group of developers agree to use names.
For example, the second method is redundant in this approach, writing queries.
select country.country_id from country
and here is a little easier to understand why to include the table alias:
select c.country_id from country c
If skillfully to shorten the alias names, then you can live with a short approach naming:
select ctry.id from country ctry
If the catch of a different kind - call or id_country field country_id.
The first option is correct from the point of view of eng. language, and the second is visually easier to keep track of the types of fields, if you put vertically.