复杂的ORDER BY语句

Question

我有这个问题：

SELECT itemID, item, note, sourceItemID, title, collectionName,
       count(tagID) as qtTag,
       count(modalityID) as qt_Modality, extra
       FROM items INNER JOIN factors ON items.itemID = factors.zotero_itemID
       WHERE (collectionID = :collectionID) AND (tagID = :tagID1 OR tagID = :tagID2) group by itemID, item, note, sourceItemID, title, collectionName, extra ORDER BY EXTRA;

现在，每个ITEM都连接到一个或多个TAGID。我需要的是以一种方式对结果进行排序，使得链接到TagID1和TagID2的ITEMS首先按顺序排列，其他的可以按EXTRA字段排序。 有可能吗？ 我尝试过使用ORDER BY CASE语句，但我无法将其解决。

这是结果的样本：

如您所见，这些项目按EXTRA字段排序。但我需要首先将ITEMS链接到TagID1和TagID2，但这些字段不会显示在结果中。我只需要订单。

我曾尝试过这段代码，但无效：

SELECT itemID, item, note, sourceItemID, title, collectionName,
       count(tagID) as qtTag,
       count(modalityID) as qt_Modality, extra
       FROM items INNER JOIN factors ON items.itemID = factors.zotero_itemID
       WHERE (collectionID = :collectionID) AND (tagID = :tagID1 OR tagID = :tagID2) group by itemID, item, note, sourceItemID, title, collectionName, extra ORDER BY CASE WHEN tagID1 = :TagID1 THEN 1 WHEN tagID2 = :tagID2 THEN 2 END,  EXTRA;

OB的。我正在使用Firebird 3.0数据库

Answer 1

试试这个;

SELECT itemID, item, note, sourceItemID, title, collectionName,
       count(tagID) as qtTag,
       count(modalityID) as qt_Modality, 
       extra
       FROM items INNER JOIN factors ON items.itemID = factors.zotero_itemID
       WHERE (collectionID = :collectionID) AND (tagID = :tagID1 OR tagID = :tagID2) 
       group by itemID, item, note, sourceItemID, title, collectionName, extra, tagID
       ORDER BY        
       (CASE
       WHEN tagID = 'tagID1' THEN 1
       WHEN tagID = 'tagID2' THEN 2
       ELSE 3
       END), extra