從查詢中獲取X最熱門的標籤

Question

$query = "SELECT tag.name, tag.id 
     FROM #__k2_tags as tag 
     LEFT JOIN #__k2_tags_xref AS xref ON xref.tagID = tag.id 
     WHERE xref.itemID IN (".implode(',', $IDs).") 
     AND tag.published = 1"; 

在xref.tagID

是標籤ID如：標籤識別：42是100倍，標籤識別：15爲90倍，標籤識別：56的10倍，我想先展示，然後42 15然後56（我想cound多少標籤是xref.tagID並序）

Answer 1

您可以group by功能嘗試：

"SELECT tag.id, count(*) 
     FROM #__k2_tags as tag 
     LEFT JOIN #__k2_tags_xref AS xref ON xref.tagID = tag.id 
     WHERE xref.itemID IN (".implode(',', $IDs).") 
     AND tag.published = 1 
GROUP BY tag.id"; 

Answer 2

試試這個：

$query = " 
SELECT * 
FROM (
    SELECT tag.name, tag.id, count(xref.id) AS tagCount 
    FROM #__k2_tags as tag 
    LEFT JOIN #__k2_tags_xref AS xref ON xref.tagID = tag.id 
    WHERE xref.itemID IN (".implode(',', $IDs).") AND tag.published = 1 
    GROUP BY tag.name, tag.id 
) 
ORDER BY tagCount"; 

通過子查詢中的GroupBy，您可以計算每種標籤類型的標籤出現量。
主要查詢需要按聚合值tagCount進行排序。