SQL 排序和列表

Question

我是 SQL 的新手，我已尽最大努力对此进行编码，但它似乎对我不起作用，因此非常感谢您的帮助。

问题表明我需要列出每个出版商出版的图书总数，然后使用出版商代码从高到低列出它们。

我已经走到这一步了；

SELECT COUNT (pub_code)
FROM Library_Books
GROUP BY pub_code
ORDER BY pub_code

如有任何帮助，我们将不胜感激

Answer 1

SELECT kb_pub_code, COUNT (kb_pub_code)    
FROM Library_Books    
GROUP BY kb_pub_code    
ORDER BY 2

Answer 2

SELECT kb_pub_code
,COUNT (*) as 'TotalBooks'
FROM Library_Books
GROUP BY kb_pub_code
ORDER BY TotalBooks desc

编辑：使用可能重复的附加信息，您可能希望使用 CTE。

With DistinctList as(
Select Distinct kb_pub_code as 'PubCode'
,kb_title as 'Title' 
FROM Library_Books)

Select PubCode
,Count(*) as 'TotalBooks'
From DistinctList
Group by PubCode
ORDER BY TotalBooks desc

Answer 3

你们很亲近：

SELECT kb_pub_code, COUNT(*) TotalBooks
FROM Library_Books
GROUP BY kb_pub_code
ORDER BY TotalBooks DESC

TotalBooks是count列的别名，统计的是每个kb_pub_code

的总行数

您可以在 ORDER BY 中引用列别名：即。ORDER BY TotalBooks DESC

请注意，如果书籍可以在 Library_Books table 中重复，您可能需要 DISTINCT 计数。类似于：

SELECT kb_pub_code, COUNT(DISTINCT title) TotalBooks
FROM Library_Books
GROUP BY kb_pub_code
ORDER BY TotalBooks DESC

Answer 4

ORDER BY DESC 将按降序排列。出版商代码应包含在结果集中 (SELECT)，否则您将不知道计数的是哪个出版商。

SELECT kb_pub_code, COUNT (kb_pub_code)    
FROM Library_Books    
GROUP BY kb_pub_code    
ORDER BY COUNT(kb_pub_code) DESC

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