Question

How are this two concepts work together ?

I have a scenario

city table

country table

city.country_id is a FK to country.id

Objective

fetch all the cities and display the country name also

My problem

the fetch method will get the cities from the table

if I need the country name I would have to do an extra search for it or an inner join
but by doing so I make extra queries when they are not necessary (display just the a city info for example)

Question

What is the right way to apply the Data Gateway Pattern in this case.

Answer 1

You should use a join if you need h associated country name. Simply add another method like fetchWithCountry.