Question

This is probably a bad example, but I think it’s quite simple.
Let’s say a web search engine (e.g. Google) is retrieving results (links to websites) of a search performed by the user and it’s supposed to order them according to a given priority of languages and countries at the same time. Say,

Language priorities

 1. English
 2. Spanish
 3. Italian
 ...

Country priorities

 1. USA
 2. England
 3. Canada
 4. Spain
 5. Mexico
 ...

So, the result would be something ordered like

Websites in english and from the USA
Websites in spanish and from the USA or in english and from England

...

Websites in italian and from Mexico (?).

A query like

SELECT url FROM websites
WHERE (
 language = english
 OR language = spanish
 OR language = italian
 ) AND (
 country = USA
 OR country = England
 OR country = Canada
 OR country = Spain
 OR country = Mexico)

obviously wouldn’t work because it provides a condition, not a priority. Using ORDER BY language or ORDER BY timezone wouldn’t work either because it orders it alphabetically. So, how is the best way to go about this in SQL?

Answer 1

Assuming that the languages and countries are in their own tables and that the websites table references those two, you order by the two fields that hold the priority of each table..

something like

SELECT 
    wesbites.url 
FROM 
    websites 
    INNER JOIN languages on websites.languageId = languages.id
    INNER JOIN countries on websites.countryId = countries.id
ORDER BY
    languages.priority,
    countries.priority