Question

I have a MySQL database which has three database tables: news_articles, languages and news_articles_languages.

• The languages table holds a record for each language the system supports
• The news_articles table holds generic information on a news article, such as ID and an attached image
• The news_articles_languages table contains localized information on a news article, and also stores revisions.

The structure of the news_articles_languages table is as follows:

id            INT       AUTO_INCREMENT
article_id    INT
language_id   INT
title         VARCHAR
friendly_name VARCHAR
content       TEXT
created       TIMESTAMP

When a news article is saved, the translations are inserted into this table with a new created column, so I can easily query previous revisions.

However, I want to be able to pull out all latest revisions based on an article ID. What would the query for this be? I’ve tried various combinations of GROUP BY and DISTINCT, but these only give one result in one language; I want all languages for a given article.

Answer 1

If the revision with the highest id is always the latest, then the following should work I think. If you can’t depend on that and need to use ‘created’, then I’m not sure!

SELECT * FROM `news_articles_languages` WHERE id IN(SELECT MAX(id) FROM `news_articles_languages` WHERE article_id = 1 GROUP BY language_id)