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Mulitple Left/Right Joins with the second one taking the first as table 1


Nok

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Hello,

my question is regarding the code below. I usually see double left joins which refer to the table1 for both LEFT JOINS (FROM cities/cities as tabl1), this one is referring to countries.code as table1 in the second LEFT JOIN which confuses me somewhat. Is the first or second LEFT JOIN excecuted first? Basically I'm asking which has priority and which table gets LEFT JOINed first.

 

SELECT cities.name AS city, urbanarea_pop, countries.name AS country,
       indep_year, languages.name AS language, percent
FROM cities
  LEFT JOIN countries
    ON cities.country_code = countries.code
  LEFT JOIN languages
    ON countries.code = languages.code
ORDER BY city, language;
 
SELECT cities.name AS city, urbanarea_pop, countries.name AS country,
       indep_year, languages.name AS language, percent
       from languages
       right join countries
        on languages.code = countries.code
        right join cities
        on countries.code = cities.country_code
order by city, language;
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