Does MySQL 5.6 Offer an Equivalent to the ANY_VALUE Function?

Is there ANY_VALUE Capability in MySQL 5.6?

You have encountered an issue while working with MySQL 5.6 in production and 5.7 in development. Specifically, you are using the GROUP BY clause, which returns an error in 5.6. In 5.7, you resolve the issue by using the ANY_VALUE function, but it is not supported in MySQL 5.6.

The query you are using is:

SELECT c.id, c.name, i.* 
 FROM countries c, images i 
WHERE i.country_id = c.id
GROUP BY c.id;

In MySQL 5.6, you get an error because non-aggregated columns are mentioned in the GROUP BY clause. One solution is to use the ANY_VALUE function, which selects a random row from the table.

SELECT c.id, c.name,
       ANY_VALUE(i.url) url, 
       ANY_VALUE(i.lat) lat, 
       ANY_VALUE(i.lng) lng 
  FROM countries c, images i
 WHERE i.country_id = c.id
 GROUP BY c.id;

However, using ANY_VALUE is not ideal as it returns an arbitrary value. A better solution is to retrieve a specific value, such as the first value:

SELECT c.id, c.name, i.*
  FROM countries c
  LEFT JOIN (
       SELECT MIN(id) id, country_id
         FROM images
        GROUP BY country_id
       ) first ON c.id = first.country_id
  LEFT JOIN images i ON first.id = i.id

This will return the first image for each country instead of a random one. Alternatively, you can disable the ONLY_FULL_GROUP_BY mode in MySQL 5.6 to allow the original query to run, but this is not recommended as it can lead to incorrect results.

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