SQL编辑年

Question

查询有效，但仅给出1985年的值。如何添加无限年数（1985-2014）

use baseball; 

SELECT CAST(tf.franchname AS CHAR(20)), s.yearID, s.lgid, AVG(s.salary) 
FROM salaries s, teams t, teamsfranchises tf 
WHERE s.teamID = t.teamID AND
t.franchID = tf.franchID AND 
s.yearID = 1985 AND
(s.lgid='AL' OR s.lgid='NL') GROUP BY tf.franchname,  s.yearID, s.lgid order BY
s.yearID;

Answer 1

您可以使用BETWEEN。

你的where子句应该是

(s.yearID BETWEEN 1985 AND 2014) and

或者，您可以使用<和>运算符：

(s.yearID >= 1984 and <= 2014)

如果出于任何原因，您没有连续的年份（您只需要5年）。 IN也可以是一个选项：

s.yearID IN (1984, 1991, 1996, 2001, 2006)    

Answer 2

您的查询在and s.yearID = 1985年内有条件过滤，您可能需要使用关键字BETWEEN进行更改，或根据需要将其删除。

Answer 3

select cast(tf.franchname as char(20)), s.yearID, s.lgid, avg(s.salary) 
from salaries s, teams t, teamsfranchises tf 
where s.teamID = t.teamID and
t.franchID = tf.franchID and 
(s.yearID between 1985  and 2014 )and 
(s.lgid='AL' OR s.lgid='NL') 
group by tf.franchname,  s.yearID, s.lgid 
order by s.yearID;

Answer 4

这是另一种观点，当没有数据时仍然希望得到零计数的年份。只需查看此link

即可

在这里你可以创建一个临时表，返回你的年份列表，即1985年到2015年，然后加入左外连接，看看魔术。

我只是得到你的查询，你也可以用接受的答案查询替换。

Declare @Startyear int = 1985
--1st approach to get continues year
;with yearlist as 
(
    select 1985 as year
    union all
    select yl.year + 1 as year
    from yearlist yl
    where yl.year + 1 <= YEAR(GetDate())
)

select year from yearlist order by year desc;

--2nd approach to get continues year
;WITH n(n) AS
(
    SELECT 0
    UNION ALL
    SELECT n+1 FROM n WHERE n <  (year(getdate()) -@Startyear)
)
SELECT year(DATEADD( YY, -n, GetDate())) 
FROM n ORDER BY n


--take anyone approach and then join with your query 
;with yearlist as 
(
    select 1985 as year
    union all
    select yl.year + 1 as year
    from yearlist yl
    where yl.year + 1 <= YEAR(GetDate())
)

select year from yearlist 
left join
(
    SELECT CAST(tf.franchname AS CHAR(20)), s.yearID, s.lgid, AVG(s.salary) 
    FROM salaries s, teams t, teamsfranchises tf 
    WHERE s.teamID = t.teamID AND
    t.franchID = tf.franchID AND 
    s.yearID = 1985 AND
    (s.lgid='AL' OR s.lgid='NL') GROUP BY tf.franchname,  s.yearID, s.lgid order BY
    s.yearID
) yourtable on yourtable.yearID  = yearlist.year
order by year desc;