显示最高价值细节的最佳方式是什么答案

【问题标题】：What is the best way to display the details of the highest value显示最高价值细节的最佳方式是什么
【发布时间】：2022-01-26 00:00:58
【问题描述】：

你好，我想知道什么是正确的方式，我被要求提供关于最年长的艺术家的信息。

FROM ListOfArtists
WHERE (DateDeceased - DateofBirth) = (SELECT 
            MAX(DateDeceased - DateofBirth)
        FROM ListOfArtists);

或者：

SELECT *
FROM ListOfArtists
ORDER BY (DateDeceased - DateofBirth) DESC
LIMIT 1

提前致谢！

【问题讨论】：

我想知道什么是正确的方法那么当你尝试时，哪一种能给你预期的结果呢？
预期的结果是像这样只介绍最年长的艺术家：ArtistID LastName FirstName Nationality DateDeceased DateOfBirth 5 Chagall Marc French 1985 1887
他们做了两件不同的事情；一个只报告 1 个结果，一个报告所有价值最高的艺术家。你要哪个？但那是 not 如何在 mysql 中获得两个日期之间的差异；这些只是几年吗？
他们都给了我同样的结果，最年长的艺术家
它们都给你相同的结果，因为你碰巧有一个特定年龄的艺术家。但是，如果您有两位活了 98 岁并且代表最长寿命的艺术家，您会从这两个查询中得到两个不同的结果。

标签： mysql sql

【解决方案1】：

如果我完全过度考虑这一点，我深表歉意，但我忍不住指出这一点。

您的第一条评论表明您只存储出生和死亡年份 -

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth
1	Botticelli	Sandro	Italian	1510	1445
2	Da Vinci	Leonardo	Italian	1519	1452
3	Buonarroti	Michelangelo	Italian	1564	1475
4	Bonestell	Chesley	American	1986	1888
5	Chagall	Marc	French	1985	1887

您的第一个查询 -

SELECT *
FROM ListOfArtists
WHERE (DateDeceased - DateofBirth) = (SELECT 
            MAX(DateDeceased - DateofBirth)
        FROM ListOfArtists);

返回 -

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth
4	Bonestell	Chesley	American	1986	1888
5	Chagall	Marc	French	1985	1887

您的第二个查询 -

SELECT *
FROM ListOfArtists
ORDER BY (DateDeceased - DateofBirth) DESC
LIMIT 1

返回 -

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth
5	Chagall	Marc	French	1985	1887

现在考虑以下版本的表格，但存储完整的出生和死亡日期 -

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth
1	Botticelli	Sandro	Italian	1510-05-17	1445-01-01
2	Da Vinci	Leonardo	Italian	1519-05-02	1452-04-15
3	Buonarroti	Michelangelo	Italian	1564-02-18	1475-03-06
4	Bonestell	Chesley	American	1986-06-11	1888-01-01
5	Chagall	Marc	French	1985-03-28	1887-07-07

您的第一个查询返回 -

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth
4	Bonestell	Chesley	American	1986-06-11	1888-01-01

您的第二个查询返回 -

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth
4	Bonestell	Chesley	American	1986-06-11	1888-01-01

更好的查询是 -

SELECT *
FROM ListOfArtists
ORDER BY DATEDIFF(DateDeceased, DateofBirth) DESC
LIMIT 1;

返回 -

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth
4	Bonestell	Chesley	American	1986-06-11	1888-01-01

下面的查询说明了两者的区别——

SELECT *, YEAR(DateDeceased) YearDied, YEAR(DateofBirth) YearBorn, (DateDeceased - DateofBirth), DATEDIFF(DateDeceased, DateofBirth) DaysOld, FLOOR(DATEDIFF(DateDeceased, DateofBirth) / 365.25) YearsOld
FROM ListOfArtists;

ArtistID	LastName	FirstName	Nationality	DateDeceased	DateOfBirth	YearDied	YearBorn	(DateDeceased - DateofBirth)	DaysOld	YearsOld
1	Botticelli	Sandro	Italian	1510-05-17	1445-01-01	1510	1445	650416	23876	65
2	Da Vinci	Leonardo	Italian	1519-05-02	1452-04-15	1519	1452	670087	24487	67
3	Buonarroti	Michelangelo	Italian	1564-02-18	1475-03-06	1564	1475	889912	32490	88
4	Bonestell	Chesley	American	1986-06-11	1888-01-01	1986	1888	980510	35955	98
5	Chagall	Marc	French	1985-03-28	1887-07-07	1985	1887	979621	35693	97

这是SQL Fiddle

【讨论】：