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T SQL Chain joins 4 tables

Here's the scenario: I have tables:

  • Articles (articleId, userId, title, datePosted)

  • ArticleTranslations (languageId, articleId, title) (not that important for this case, but I show it anyway)

  • ArticleSections (articleSectionId, articleId, sectionId)

  • sections (sectionId, content, ...)

  • sectionsAdditionalInfo (sectionId, isApproved)

What I am doing is selecting some articles from userId articles in a way:

SELECT article.articleId, article.userId, ArticleTranslations.title, article.datePosted
FROM Articles
LEFT OUTER JOIN ArticleTranslations ON Article.articleId= ArticlesTranslations.articleId AND ArticlesTranslations.languageId=@languageId
WHERE Articloes.userId=@userId
    ORDER BY
CASE WHEN @sortDirection = 'DD' THEN datePosted END DESC,   -- by date posted
CASE WHEN @sortDirection = 'DA' THEN datePosted END,
CASE WHEN @sortDirection = 'ND' THEN title END DESC,        -- sort by name
CASE WHEN @sortDirection = 'NA' THEN title END, 
CASE WHEN @sortDirection = 'SD' THEN ArticleTranslations.isApproved END DESC, -- is article aproved?
CASE WHEN @sortDirection = 'SA' THEN ArticleTranslations.isApproved END,
CASE WHEN @sortDirection = 'ID' THEN areAllSectionsApproved END DESC,   -- sort by information if sections are all approved - within the article?
CASE WHEN @sortDirection = 'IA' THEN areAllSectionsApproved END

Please note that I have left some of the information to make my question clearer.

Now what I would like to do is select a different attribute (for each article returned in the SQL above): areAllArticleSectionsApproved

I have compiled the SQL separately, but I would like this to be returned for every row:

    SELECT CASE WHEN COUNT(sectionsAdditionalInfo.sectionId) > 0 THEN 0 ELSE 1 END AS areAllSectionsApproved
    FROM ArticleSections
    LEFT OUTER JOIN sectionsAdditionalInfo ON ArticleSections.sectionId = sectionsAdditionalInfo.sectionId 
    WHERE articleId=@articleId AND sectionsAdditionalInfo.isApproved=0

I tried to nest this SQL in some sense:

    SELECT (outer SQL) .....
    a.*(
    nested SQL - second one I posted here
    ) as a

but it didn't work at all.

I am using SQL Server 2008.

Any hint on how to fix this would be greatly appreciated;)

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1 answer


Without fully understanding your data and the desired results, something like this should work using your above query and joining your second query as a subquery:

SELECT article.articleId, 
       article.userId, 
       ArticleTranslations.title, 
       article.datePosted,
       t.areAllSectionsApproved
FROM Articles
      LEFT OUTER JOIN ArticleTranslations 
          ON Article.articleId= ArticlesTranslations.articleId 
          AND ArticlesTranslations.languageId=@languageId
      LEFT JOIN (
         SELECT 
           articleId, 
           CASE 
              WHEN COUNT(sectionsAdditionalInfo.sectionId) > 0 
              THEN 0 
              ELSE 1 
           END AS areAllSectionsApproved
         FROM ArticleSections
             LEFT OUTER JOIN sectionsAdditionalInfo 
                ON ArticleSections.sectionId = sectionsAdditionalInfo.sectionId 
         WHERE sectionsAdditionalInfo.isApproved=0
         GROUP BY articleId
    ) t ON articles.articleId = t.articleId
WHERE Articloes.userId=@userId
ORDER BY
   CASE WHEN @sortDirection = 'DD' THEN datePosted END DESC,   -- by date posted
   CASE WHEN @sortDirection = 'DA' THEN datePosted END,
   CASE WHEN @sortDirection = 'ND' THEN title END DESC,        -- sort by name
   CASE WHEN @sortDirection = 'NA' THEN title END, 
   CASE WHEN @sortDirection = 'SD' THEN ArticleTranslations.isApproved END DESC, -- is article aproved?
   CASE WHEN @sortDirection = 'SA' THEN ArticleTranslations.isApproved END,
   CASE WHEN @sortDirection = 'ID' THEN areAllSectionsApproved END DESC,   -- sort by information if sections are all approved - within the article?
   CASE WHEN @sortDirection = 'IA' THEN areAllSectionsApproved END


Good luck.

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