Question

I’m trying to find an SQL query to end up with 1 row containing an article title and its associated keywords.

Articles
-ArticleID PK
-ArticleTitle
-ArticleBody

Keywords
-KeywordID PK
-Keyword UNIQUE

Keyword_Article
-KeywordID PK
-ArticleID PK

Is this possible without multiple queries in PHP?

What I have which gives me as many rows as there are keywords per article

SELECT Article.ArticleID, 
Article.ArticleTitle, 
Keywords.Keyword, 
Keywords.KeywordID
FROM Article 
LEFT JOIN Keyword_Article
ON (Keyword_Article.ArticleID = Article.ArticleID)
LEFT JOIN Keywords
ON (Keyword_Article.KeywordID = Keywords.KeywordID)
WHERE Article.ArticleID='example'

I’m curious to see how and if it can be done with 1 SQL query.

Answer 1

You cannot have a SQL statement that returns a variable number of columns. So, you can’t put each keyword in a separate column where the number of columns would vary by the article (unless you use dynamic SQL).

You can concatenate the keywords together into a single column using group_concat:

SELECT Article.ArticleID, Article.ArticleTitle, 
       group_concat(Keywords.Keyword separator ', ') as keywords
FROM Article  LEFT JOIN
     Keyword_Article
     ON Keyword_Article.ArticleID = Article.ArticleID EFT JOIN
     Keywords
     ON Keyword_Article.KeywordID = Keywords.KeywordID
WHERE Article.ArticleID = 'example'